Category: Meeting Updates

Late Breaking Abstract – ESMO 2020. VERZENIO® Plus Endocrine Therapy Improves Disease Free Survival in Early Breast Cancer

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SUMMARY: Breast cancer is the most common cancer among women in the US and about 1 in 8 women 12%) will develop invasive breast cancer during their lifetime. Approximately 279,100 new cases of invasive breast cancer will be diagnosed in 2020 and about 42,690 individuals will die of the disease largely due to metastatic recurrence. About 70% of breast tumors express Estrogen Receptors and/or Progesterone Receptors, and Hormone Receptor (HR)-positive/HER2-negative breast cancer is the most frequently diagnosed molecular subtype. Majority of these patients are diagnosed with early stage disease and are often cured with a combination of surgery, radiotherapy, chemotherapy, and hormone therapy. However approximately 20% of patients will experience local recurrence or distant relapse during the first 10 years of treatment. This may be more relevant for those with high risk disease, among whom the risk of recurrence is even greater during the first 2 years while on adjuvant endocrine therapy, due to primary endocrine resistance. More than 75% of the early recurrences are seen at distant sites.

Cyclin Dependent Kinases (CDK) play a very important role to facilitate orderly and controlled progression of the cell cycle. Genetic alterations in these kinases and their regulatory proteins have been implicated in various malignancies. CDK 4 and 6 phosphorylate RetinoBlastoma protein (RB), and initiate transition from the G1 phase to the S phase of the cell cycle. RetinoBlastoma protein has antiproliferative and tumor-suppressor activity and phosphorylation of RB protein nullifies its beneficial activities. CDK4 and CDK6 are activated in hormone receptor positive breast cancer, promoting breast cancer cell proliferation. Further, there is evidence to suggest that endocrine resistant breast cancer cell lines depend on CDK4 for cell proliferation. The understanding of the role of Cyclin Dependent Kinases in the cell cycle, has paved the way for the development of CDK inhibitors.MOA-of_ABEMACICLIB

VERZENIO® (Abemaciclib) is an oral, selective inhibitor of CDK4 and CDK6 kinase activity, and prevents the phosphorylation and subsequent inactivation of the Rb tumor suppressor protein, thereby inducing G1 cell cycle arrest and inhibition of cell proliferation. VERZENIO® is structurally distinct from other CDK 4 and 6 inhibitors (such as Ribociclib and Palbociclib) and is 14 times more potent against cyclin D1/CDK 4 and cyclin D3/CDK 6, in enzymatic assays, but potentially less toxic than earlier pan-CDK inhibitors. At higher doses, only VERZENIO® causes significant cancer cell death, compared with other CDK4/6 inhibitors, suggesting that this drug may be affecting proteins, other than CDK4/6. Additionally, preclinical studies have demonstrated that VERZENIO® may have additional therapeutic benefits for a subset of tumors that are unresponsive to treatment or have grown resistant to other CDK4/6 inhibitors. It has also been shown to cross the blood-brain barrier.

VERZENIO® is presently approved by the FDA as monotherapy as well as in combination with endocrine therapy for patients with HR-positive, HER2- negative advanced breast cancer. The addition of VERZENIO® to FASLODEX® resulted in a statistically significant improvement in Overall Survival among patients with HR-positive, HER2-negative advanced breast cancer, who had progressed on prior endocrine therapy. The goal of monarchE was to evaluate the additional benefit of adding a CDK4/6 inhibitor to endocrine therapy in the adjuvant setting, for patients with HR-positive, HER2-negative early breast cancer.

The international monarchE trial, is an open-label, randomized, Phase III study, which included 5637 patients, who were pre- and postmenopausal, with HR-positive, HER2-negative early breast cancer, and with clinical and/or pathologic risk factors that rendered them at high risk for relapse. The researchers defined high risk as the presence of four or more positive axillary lymph nodes, or 1-3 three positive axillary lymph nodes, with either a tumor size of 5 cm or more, histologic Grade 3, or centrally tested high proliferation rate (Ki-67 of 20% or more). Following completion of primary therapy which included both adjuvant and neoadjuvant chemotherapy and radiotherapy, patients were randomly assigned (1:1) to VERZENIO® 150 mg orally twice daily for 2 years plus 5 to 10 years of physicians choice of endocrine therapy as clinically indicated (N=2808), or endocrine therapy alone (N=2829). The median patient age was 51 years, about 43% of the patients were premenopausal, and 95% of patients had prior chemotherapy. Approximately 60% of patients had 4 or more positive lymph nodes. The Primary endpoint was Invasive Disease Free Survival (IDFS), and Secondary end points included distant Relapse Free Survival, Overall Survival, and safety. The authors in this publication reported the first results, following a preplanned interim analysis.

The addition of VERZENIO® to endocrine therapy resulted in an IDFS of 92.2% at 2 years compared with 88.7% with endocrine therapy alone, and this was statistically significant (HR=0.75; P=0.01). This suggested a 25% reduction in the risk of developing an IDFS event, relative to endocrine therapy alone, and a 3.5% absolute improvement in 2-year IDFS rates. VERZENIO® plus endocrine therapy combination also reduced the risk of metastatic recurrence especially in bone and liver (distant recurrences or Distant Relapse Free Survival) by a clinically meaningful 28% compared to endocrine therapy alone. This clinical benefit was observed in all prespecified subgroups, and among the 43% of patients who were premenopausal at diagnosis, there was a significant 37% reduction in the risk of recurrence compared to endocrine therapy alone. The safety was consistent with the known profile of VERZENIO® and included diarrhea, neutropenia, and fatigue. Diarrhea was well managed with antidiarrheal medications and dose adjustments.

It was concluded that VERZENIO® when combined with endocrine therapy demonstrated a significant improvement in Invasive Disease Free Survival, compared to endocrine therapy alone, in patients with high risk HR-positive, HER2-negative early breast cancer. The researchers also plan to look at genomic signatures in the tissue and plasma samples of enrolled patients and response to VERZENIO®.

Abemaciclib Combined With Endocrine Therapy for the Adjuvant Treatment of HR+, HER2−, Node-Positive, High-Risk, Early Breast Cancer (monarchE). Johnston SRD, Harbeck N, Hegg R, et al. DOI: 10.1200/JCO.20.02514 Journal of Clinical Oncology – published online before print September 20, 2020

First Line KEYTRUDA® plus Chemotherapy Significantly Improves PFS in PD-L1-High Triple Negative Breast Cancer

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SUMMARY: Breast cancer is the most common cancer among women in the US and about 1 in 8 women (13%) will develop invasive breast cancer during their lifetime. Approximately 276,480 new cases of invasive female breast cancer will be diagnosed in 2020 and about 42,170 women will die of the disease. Triple Negative Breast Cancer (TNBC) is a heterogeneous, molecularly diverse group of breast cancers and are ER (Estrogen Receptor), PR (Progesterone Receptor) and HER2 (Human Epidermal Growth Factor Receptor-2) negative. TNBC accounts for 15-20% of invasive breast cancers, with a higher incidence noted in young patients and African American females. It is usually aggressive, and tumors tend to be high grade, and patients with TNBC are at a higher risk of both local and distant recurrence and often develop visceral metastases. Those with metastatic disease have one of the worst prognoses of all cancers with a median Overall Survival of 13 months. The majority of patients with TNBC who develop metastatic disease do so within the first 3 years after diagnosis, whereas those without recurrence during this period of time have survival rates similar to those with ER-positive breast cancers. The lack of known recurrent oncogenic drivers in patients with metastatic TNBC, presents a major therapeutic challenge. Overall survival among patients with pretreated metastatic TNBC has not changed over the past 2 decades and standard chemotherapy is associated with low response rates of 10-15% and a Progression Free Survival (PFS) of only 2-3 months.

KEYTRUDA® (Pembrolizumab) is a fully humanized, Immunoglobulin G4, anti-PD-1, monoclonal antibody, that binds to the PD-1 receptor and blocks its interaction with ligands PD-L1 and PD-L2. It thereby reverses the PD-1 pathway-mediated inhibition of the immune response and unleashes the tumor-specific effector T cells. The rationale for combining chemotherapy with immunotherapy is that cytotoxic chemotherapy releases tumor-specific antigens, and immune checkpoint inhibitors such as KEYTRUDA® when given along with chemotherapy can enhance endogenous anticancer immunity.

Single agent KEYTRUDA® in metastatic TNBC demonstrated durable antitumor activity in several studies, with Objective Response Rates (ORRs) ranging from 10% to 21% and improved clinical responses in patients with higher PD-L1 expression. When given along with chemotherapy as a neoadjuvant treatment for patients with high-risk, early-stage TNBC, KEYTRUDA® combination achieved Pathological Complete Response rate of 65%, regardless of PD-L1 expression. Based on this data, KEYTRUDA® in combination with chemotherapy was studied, for first-line treatment of triple-negative metastatic breast cancer.

KEYNOTE-355 is a randomized, double-blind, phase III study, which evaluated the benefit of KEYTRUDA® in combination with one of the three different chemotherapy regimens, nab-Paclitaxel, Paclitaxel, or the non-taxane containing Gemzar/Carboplatin, versus placebo plus one of the three chemotherapy regimens, in patients with previously untreated or locally recurrent inoperable metastatic TNBC. In this study, 847 patients were randomized 2:1 to receive either KEYTRUDA® 200 mg IV on day 1 of each 21-day cycle along with either nab-paclitaxel 100 mg/m2 IV on days 1, 8 and 15 of each 28-day cycle, Paclitaxel 90 mg/m2 IV on days 1, 8 and 15 of each 28-day cycle, or Gemcitabine 1000 mg/m2 IV plus Carboplatin AUC 2 IV on days 1 and 8 of each 21-day cycle (N= 566) or placebo along with one of the three chemotherapy regimens (N= 281). This study was not designed to compare the efficacy of the different chemotherapy regimens. Treatment was continued until disease progression. Patients were stratified by chemotherapy, PD-L1 tumor expression (CPS of 1 or higher versus CPS of less than 1), and prior treatment with the same class of neoadjuvant/adjuvant chemotherapy (yes vs no). The baseline characteristics of treatment groups were well-balanced. The co-Primary end points of the trial were Progression Free Survival (PFS) and Overall Survival (OS) in patients with PD-L1-positive tumors, and in all patients. Secondary end points were Objective Response Rate (ORR), Duration of Response, Disease Control Rate, and safety. The median follow up for patients assigned to receive KEYTRUDA® was 17.5 months and 15.5 months for the placebo group. The authors reported the results from an interim analysis conducted by an Independent Data Monitoring Committee (IDMC).

KEYTRUDA® in combination with chemotherapy, significantly improved PFS in patients with CPS (Combined Positive Score) of 10 or greater. The median PFS was 9.7 months for KEYTRUDA® plus chemotherapy, compared with 5.6 months for placebo plus chemotherapy (HR=0.65, P=0.0012). This represented a 35% reduction in the risk of disease progression. Among patients with CPS of 1 or greater, the median PFS was 7.6 months for KEYTRUDA® plus chemotherapy, compared with 5.6 months for the placebo plus chemotherapy arm (HR= 0.74; P=0.0014). This however based on prespecified statistical criteria, was not considered statistically significant. Among the entire Intention-To-Treat (ITT) population, the median PFS was 7.5 months in the KEYTRUDA® plus chemotherapy group, compared with 5.6 months for chemotherapy plus placebo group (HR=0.82). Formal statistical significance was not tested in the ITT population. Overall Survival data are pending. Adverse Events (AEs) were similar in both treatment groups, although immune-related AEs occurred at a higher incidence in the KEYTRUDA® arm.

It was concluded that KEYTRUDA® in combination with several chemotherapy regimens, showed a statistically significant and clinically meaningful improvement in PFS, compared with chemotherapy alone, in patients with previously untreated locally recurrent, inoperable or metastatic TNBC, whose tumors expressed PD-L1 with a Combined Positive Score (CPS) of 10 or more. This data may be particularly relevant for patients who may have received a taxane in the adjuvant setting within a year, and could be more appropriately treated with a non-taxane regimen, in combination with KEYTRUDA®.

KEYNOTE-355: Randomized, double-blind, phase III study of pembrolizumab + chemotherapy versus placebo + chemotherapy for previously untreated locally recurrent inoperable or metastatic triple-negative breast cancer. Cortes J, Cescon DW, Rugo HS. et al. J Clin Oncol 38: 2020 (suppl; abstr 1000)

PSMA-Targeted Imaging for Biochemically Recurrent Prostate Cancer

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SUMMARY: Prostate cancer is the most common cancer in American men with the exclusion of skin cancer, and 1 in 9 men will be diagnosed with prostate cancer during their lifetime. It is estimated that in the United States, about 191,930 new cases of prostate cancer will be diagnosed in 2020 and 33,330 men will die of the disease.

The major source of PSA (Prostate Specific Antigen) is the prostate gland and the PSA levels are therefore undetectable within 6 weeks after Radical Prostatectomy. Similarly, following Radiation Therapy, there is a gradual decline in PSA before reaching a post treatment nadir. A detectable PSA level after Radical Prostatectomy, or a rising PSA level following Radiation Therapy, is considered PSA failure or biochemical recurrence. Approximately 35% of the patients with prostate cancer will experience PSA only relapse within 10 years of their primary treatment and a third of these patients will develop documented metastatic disease within 8 years following PSA only relapse.Defining-Biochemical-Recurrence

Rising PSA is therefore a sign of recurrent disease and identifying the site of recurrence can be of immense value for the clinician and can help determine the best course of therapy. The diagnostic accuracy of standard imaging tests, for the identification of sites of recurrence in patients with biochemical recurrence, is low. Almost 90% of the standard imaging tests such as CT/MRI and Bone Scan may be negative. More accurate non-invasive imaging techniques for the detection of recurrent tumor is therefore an unmet need. Prostascint, a Single Photon Emission Computerized Tomography (SPECT) radiopharmaceutical agent, was approved in 1999 for the diagnostic imaging of post-prostatectomy patients with a rising PSA. PET (Positron Emission Tomography) scans have largely superseded this study. FluDeoxyGlucose F18 (FDG), a glucose analogue is the most widely used PET radiotracer, but is not generally used as an imaging agent in prostate cancer. This is because good and reliable quality images are not feasible due to indolent growth of prostate cancers and the high urinary excretion of FDG. The other PET radiotracer that is available, Choline C11, has been shown to improve cancer detection in men with biochemical recurrent prostate cancer, but this agent has a short half life of 20 minutes, requires greater patient preparation including 6 hours of fasting prior to administration of Choline C11, delivers higher radiation dose to patients and image quality is poor. The FDA in 2016 approved AXUMIN® (Fluciclovine F18), a novel molecular radiopharmaceutical diagnostic agent, for PET imaging in men with suspected prostate cancer recurrence, based on elevated PSA levels, following prior treatment. This study however is less likely to be positive with PSA less than 1 ng/mL, unless the doubling time is rapid. There is also higher false positive rate within the intact or treated prostate gland, and uptake may be absent in densely sclerotic lesions. Current imaging modalities are therefore inadequate for localizing and characterizing occult disease in men with biochemically recurrent prostate cancer.

F-18 DCFPyL is a novel PET imaging agent that binds selectively with high affinity to Prostate-Specific Membrane Antigen (PSMA), which is overexpressed in prostate cancer cells. CONDOR is a prospective, multicenter, randomized, Phase III trial, conducted to evaluate the diagnostic performance of PET/CT imaging with F-18 DCFPyL, a radiopharmaceutical targeting the extracellular domain of PSMA. This study enrolled 208 men at 14 sites in the US and Canada, with a rising PSA level after definitive therapy and negative or equivocal standard-of-care imaging (eg, CT, MRI, bone scintigraphy). PET/CT imaging was performed 1-2 hours following administration of a single dose of F-18 DCFPyL. The median age was 68 yrs and the median time from diagnosis was 71 months. Approximately 50% of all patients had undergone Radical Prostatectomy, 35% underwent Radical Prostatectomy and Radiation Therapy, 15% had only received RadioTherapy, and 28% received at least one systemic therapy for their prostate cancer. Approximately 74% of patients had a total Gleason score below 8. All enrolled patients had biochemically recurrent metastatic Castration-Resistant Prostate Cancer, and a PSA of at least 0.2 ng/mL following radical prostatectomy, or at least 2 ng/mL over the nadir following prior Radiation Therapy, Cryotherapy or systemic therapy. The median PSA was 0.8 ng/mL, (PSA level at which most decisions about subsequent salvage focal or systemic therapies are made) and 31% of patients had a PSA of at least 2.0 ng/mL. All enrolled patients had no previous radiologic findings. The Primary endpoint was Correct Localization Rate of occult disease, as determined by three independent reviewers, and the Secondary endpoint was the impact of F-18 DCFPyL PET/CT imaging results on management of enrolled patients in this study.

The study met its Primary endpoint and the Correct Localization Rate of occult disease or the Positive Predictive Value ranged from 84.8% to 87% for the three independent reviewers. The Correct Localization Rate of occult disease was maintained regardless of PSA values and the F-18 DCFPyL PET/CT imaging detected disease even at the lowest of PSA values. Regarding the Secondary endpoint of impact of F-18 DCFPyL PET/CT imaging on treatment, 64% of patients had a change in management due to findings noted on the imaging study, of which 78% were attributable to positive findings on the imaging study, and 21.4% to negative findings on F-18 DCFPyL PET/CT imaging study. Specific changes in the treatment management included change in the goal of patients disease management from a noncurative approach to a curative salvage local therapy in 21% of patients, 28% changed from receiving salvage local therapy to systemic therapy or added systemic therapy, 23.9% changed from observation status to initiation of therapy and 4.4% changed from planned treatment to observation alone.

It was concluded that PSMA-targeted F-18 DCFPyL PET/CT imaging detected and localized occult disease in most men with biochemical recurrence, presenting with negative or equivocal findings on conventional imaging. Further, F-18 DCFPyL PET/CT imaging provided actionable information that led to change in treatment plans for the majority of patients, thus providing evidence that PSMA PET imaging may be valuable in men with recurrent or suspected metastatic prostate cancer.

Impact of PSMA-targeted imaging with 18F-DCFPyL-PET/CT on clinical management of patients (pts) with biochemically recurrent (BCR) prostate cancer (PCa): Results from a phase III, prospective, multicenter study (CONDOR). Morris MJ, Carroll PR, Saperstein L, et al. DOI: 10.1200/JCO.2020.38.15_suppl.5501 Journal of Clinical Oncology 38, no. 15_suppl (May 20, 2020) 5501-5501.

ENHERTU® Demonstrates Promising Clinical Activity in HER2 Positive Non-Small Cell Lung Cancer

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SUMMARY: Lung cancer is the second most common cancer in both men and women and accounts for about 14% of all new cancers and 27% of all cancer deaths. The American Cancer Society estimates that for 2020, about 228, 820 new cases of lung cancer will be diagnosed and 135,720 patients will die of the disease. Lung cancer is the leading cause of cancer-related mortality in the United States. Non-Small Cell Lung Cancer (NSCLC) accounts for approximately 85% of all lung cancers. Of the three main subtypes of NSCLC, 30% are Squamous Cell Carcinomas (SCC), 40% are Adenocarcinomas and 10% are Large Cell Carcinomas. With changes in the cigarette composition and decline in tobacco consumption over the past several decades, Adenocarcinoma now is the most frequent histologic subtype of lung cancer.

The HER or erbB family of receptors consist of HER1, HER2, HER3 and HER4. HER2 is a Tyrosine Kinase Receptor expressed on the surface of several tumor types including breast, gastric, lung and colorectal cancers. It is a growth-promoting protein and HER2 overexpression/HER2 gene amplification is often associated with aggressive disease and poor prognosis in certain tumor types. Other HER2 gene alterations such as HER2 mutations, as distinct molecular targets, have been identified in 2-4% of patients with NSCLC, specifically with adenocarcinoma histology. These acquired HER2 gene mutations have been independently associated with cancer cell growth and poor prognosis. There are currently no therapies approved specifically for the treatment HER2 mutant NSCLC, and is therefore an unmet need.Mechanism-of-Action-ENHERTU

ENHERTU® (Trastuzumab Deruxtecan) is an Antibody-Drug Conjugate (ADC) composed of a humanized monoclonal antibody specifically targeting HER2, with the amino acid sequence similar to HERCEPTIN® (Trastuzumab), attached to a potent cytotoxic Topoisomerase I inhibitor payload by a cleavable tetrapeptide-based linker. ENHERTU® has a favorable pharmacokinetic profile and the tetrapeptide-based linker is stable in the plasma and is selectively cleaved by cathepsins that are up-regulated in tumor cells. Unlike KADCYLA® (ado-Trastuzumab emtansine), which is also an Antibody-Drug Conjugate, ENHERTU® has a higher drug-to-antibody ratio (8 versus 4), the released payload easily crosses the cell membrane with resulting potent cytotoxic effect on neighboring tumor cells regardless of target expression, and the released cytotoxic agent (payload) has a short half-life, minimizing systemic exposure. ENHERTU® is approved in the US for the treatment of adult patients with unresectable or metastatic HER2 positive breast cancer who received two or more prior anti-HER2 based regimens, based on the DESTINY-Breast01 trial.

DESTINY-Lung01 is an ongoing, global, multicenter, open-label, two-cohort, Phase II study, evaluating the safety and efficacy of ENHERTU® in 170 patients with HER2 mutant or HER2 overexpressing (defined as ImmunoHistoChemistry-IHC 3+ or IHC 2+), unresectable and metastatic non-squamous NSCLC. Eligible patients could not have received prior HER2-targeted therapy, with the exception of pan-HER TKIs. Patients were enrolled into 2 cohorts. The first cohort enrolled patients with HER2-expressing tumors as defined by IHC 3+ or 2+ (N = 42). The second cohort included patients whose tumors harbored a HER2 mutation as determined by a local laboratory test (N = 42). Enrolled patients had a median of two prior lines of therapy with majority of patients receiving platinum-based chemotherapy (90.5%), anti-PD-1 or PD-L1 treatment (54.8%) and 19% receiving Docetaxel. Patients received ENHERTU® 4.6 mg/kg every 3 weeks by intravenous infusion. The 42 patients included in the second cohort had a median age of 63 years, 64.3% of patients were female, and 45.2% had CNS metastases. For the majority of patients (90.5%), HER2 mutation was located in the kinase domain. The Primary endpoint was confirmed Objective Response Rate (ORR). Additional endpoints included Disease Control Rate (DCR), Duration of Response (DoR), Progression Free Survival (PFS), and safety. The authors reported data for the cohort with HER2 mutations (second cohort), after a median follow up of 8.0 months.

The ORR was 61.9%, with 2.4% Complete Response, 59.5% Partial Response, and stable disease noted in 28.6% of patients. The Disease Control Rate was 90.5%. The median PFS was 14 months. The median Duration of Response and Overall Survival (OS) had not yet been reached at the time of data cut-off. The most common Grade 3 or higher treatment related Adverse Events were neutropenia and anemia. Confirmed treatment-related Interstitial Lung Disease (ILD) and pneumonitis were noted in approximately 12% of patients and were all Grade 2 and there were no deaths. Nonetheless, ILD is an important identified risk for patients treated with ENHERTU® and requires careful monitoring and management.

It was concluded that ENHERTU® demonstrated promising clinical activity in this interim analysis, with a high Objective Response Rate and durable responses, in a heavily pretreated population of patients with HER2-mutated NSCLC.

Trastuzumab deruxtecan (T-DXd; DS-8201) in patients with HER2-mutated metastatic non-small cell lung cancer (NSCLC): Interim results of DESTINY-Lung01. Smit EF, Nakagawa K, Nagasaka M, et al. J Clin Oncol 38: 2020 (suppl; abstr 9504).

PIQRAY® Effective after Progression on CDK Inhibition in Advanced Breast Cancer

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SUMMARY: Breast cancer is the most common cancer among women in the US and about 1 in 8 women (13%) will develop invasive breast cancer during their lifetime. Approximately 276,480 new cases of invasive female breast cancer will be diagnosed in 2020 and about 42,170 women will die of the disease. Approximately 6% of newly diagnosed breast cancer patients present with Stage IV disease and about half of patients with primary breast cancer will progress later to the metastatic stage. About 70% of breast tumors express Estrogen Receptors and/or Progesterone Receptors and Hormone Receptor (HR)-positive/HER2-negative breast cancer is the most frequently diagnosed molecular subtype. Most of these patients with advanced disease in the current era are treated with a combination of CDK4/6 inhibitor and endocrine therapy (often an oral Aromatase Inhibitor), based on survival data. However, resistance to these regimens typically develops in a majority of the patients.

The PhosphoInositide 3-Kinase (PI3K) pathway is an intracellular signaling pathway important in the regulation of cancer cell proliferation and metastasis. PI3K is a lipid kinase and has four distinct isoforms – alpha, beta, gamma and delta, which play a unique role in the survival of different tumor types and establishment of supportive tumor microenvironments. The alpha and beta isoforms are expressed in a wide variety of tissues whereas the gamma and delta isoforms are primarily expressed in hematopoietic cells such as B and T cells. The PI3K alpha isoform is particularly important in breast cancer and plays an important role in tumorigenesis, supporting tumor angiogenesis and stromal interactions, making this a viable target. PIK3CA is an oncogene that codes for the alpha isoform of PI3K, (PI3Kα), more specifically for the alpha isoform of p110. The PI3k pathway is the most frequently altered pathway in human cancers including breast cancer, and has been implicated in disease progression in a significant number of patients with breast cancer. Activation of the PI3K pathway in breast cancer has been associated with resistance to endocrine therapy and disease progression. Approximately 40% of patients with Hormone Receptor positive (HR+), HER2-negative breast cancers, harbor activating mutations in the PIK3CA isoform of PI3K, which is the most common mutation in HR+ breast cancer. Patients with advanced breast cancer harboring PIK3CA mutations typically have a poor prognosis. This provides a strong rationale for targeting the PI3K pathway in breast cancer.Alpelisib-Mechanism-of-Action

PIQRAY® is an oral, alpha-specific PI3K inhibitor that specifically inhibits PIK3 in the PI3K/AKT kinase signaling pathway. Further, it was shown in preclinical studies that cancer cells with PIK3CA mutations are more sensitive to PIQRAY® than those without the mutation, across a broad range of tumor types. In the SOLAR-1 Phase III trial, there was a 35% improvement in Progression Free Survival (PFS) in patients randomized to PIQRAY® plus FASLODEX®, compared to the placebo plus FASLODEX® group, among postmenopausal patients with PIK3CA-mutated, HR+/HER2- negative, advanced breast cancer, who had progressed on or following prior Aromatase Inhibitor (AI) treatment with or without a CDK 4/6 inhibitor. However in this study, only 6% had received prior CDK4/6 inhibitor therapy and there is presently limited data available, to inform treatment decisions in patients who progress on AI and CDK 4/6 inhibitor combination.

BYLieve is an ongoing, prospective, open-label, Phase II, non-comparative trial, which evaluated the benefit of PIQRAY&reg in combination with endocrine therapy in patients with HR+, HER-negative, PIK3CA-mutated, advanced breast cancer, who progressed on or after a prior therapy including CDK inhibitor. This study included 3 patient cohorts– Cohort A included patients who received a CDK4/6 inhibitor plus an AI as immediate prior therapy, Cohort B included patients who received a CDK4/6 inhibitor plus FASLODEX® (Fulvestrant) as immediate prior therapy, and Cohort C included patients who progressed on/after an AI and received chemotherapy or endocrine therapy as immediate prior treatment.

The authors in this publication shared findings from Cohort A group of patients, who had received CDK4/6 inhibitor plus an AI as their immediate prior therapy. Cohort A enrolled 127 patients of whom 121 patients had centrally confirmed PIK3CA mutation. Patients in Cohort A received PIQRAY® 300 mg orally once daily along with FASLODEX® 500 mg IM on Day 1 and 15 of cycle 1 followed by Day 1 treatment, of each 28 day cycle thereafter. The median patient age was 58 years. Seventy percent (70%) of patients had received one prior metastatic regimen, none of the patients had received FASLODEX® as a first-line metastatic agent, and 60% of patients had secondary endocrine resistance. The median follow up was 11.7 months. The Primary endpoint was proportion of patients alive without disease progression at 6 months. Secondary end points included Progression Free Survival (PFS), Overall Response Rate (ORR), Overall Survival (OS), and safety.

The Primary endpoint was met and the proportion of patients with confirmed PIK3CA mutation and without disease progression at 6 months was 50.4%. The median PFS was 7.3 months. Among the 121 patients in Cohort A with a confirmed PIK3CA mutation, the response rate, which was all partial responses was 17.4%, and 45.5% achieved stable disease.

Although the BYLieve trial did not have a control group to allow comparing patients in Cohort A to patients receiving other standard therapies, the authors conducted a weighted/matched analysis between the patients in Cohort A of the BYLieve trial and a Real-World similar group of 95 patients with HR+, HER2-negative, PIK3CA-mutated advanced breast cancer, who were treated with standard therapies. The Real-World patient data was obtained from the de-identified clinic-genomic database of Flatiron Health and Foundation Medicine. These 95 patients had received a wide range of regimens, with the most frequent being XELODA® (Capecitabine) monotherapy, FASLODEX® monotherapy, FASLODEX® plus IBRANCE® (Palbociclib), AFINITOR® (Everolimus) plus AROMASIN® (Exemestane), FASLODEX® plus FEMARA® (Letrozole), and IBRANCE® monotherapy.

Unadjusted results showed a median PFS of 7.3 months in BYLieve Cohort A versus 3.6 months in the Real-World cohort. Similar outcomes were noted when data were weighted by odds, propensity score matching, and exact matching.

It was concluded that the BYLieve trial is continuing to show clinically meaningful efficacy with a combination of PIQRAY® and FASLODEX® in HR+, HER2-negative, PIK3CA-mutated advanced breast cancer, post CDK inhibitor treatment, building further on the findings of SOLAR-1 trial. The matched analysis comparing BYLieve with Real-World Data in the post-CDK4/6 inhibitor setting, further supports use of PIQRAY® plus FASLODEX® for this patient group.

Alpelisib (ALP) + fulvestrant (FUL) in patients (pts) with PIK3CA-mutated (mut) hormone receptor-positive (HR+), human epidermal growth factor receptor 2-negative (HER2–) advanced breast cancer (ABC) previously treated with cyclin-dependent kinase 4/6 inhibitor (CDKi) + aromatase inhibitor (AI): BYLieve study results. Rugo HS, Lerebours F, Ciruelos E, et al. J Clin Oncol 38: 2020 (suppl; abstr 1006).

Overall Survival Benefit with Frontline OPDIVO® plus YERVOY® and Limited Chemotherapy in NSCLC

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SUMMARY: The FDA on May 26, 2020, approved the combination of OPDIVO® (Nivolumab) plus YERVOY® (Ipilimumab) and 2 cycles of Platinum-doublet chemotherapy as first-line treatment for patients with metastatic or recurrent Non-Small Cell Lung Cancer (NSCLC), with no Epidermal Growth Factor Receptor (EGFR) or Anaplastic Lymphoma Kinase (ALK) genomic tumor aberrations. Lung cancer is the second most common cancer in both men and women and accounts for about 14% of all new cancers and 27% of all cancer deaths. The American Cancer Society estimates that for 2020, about 228, 820 new cases of lung cancer will be diagnosed and 135,720 patients will die of the disease. Lung cancer is the leading cause of cancer-related mortality in the United States. Non-Small Cell Lung Cancer (NSCLC) accounts for approximately 85% of all lung cancers. Of the three main subtypes of NSCLC, 30% are Squamous Cell Carcinomas (SCC), 40% are Adenocarcinomas and 10% are Large Cell Carcinomas. With changes in the cigarette composition and decline in tobacco consumption over the past several decades, Adenocarcinoma now is the most frequent histologic subtype of lung cancer.

Immune checkpoints are cell surface inhibitory proteins/receptors that are expressed on activated T cells. They harness the immune system and prevent uncontrolled immune reactions by switching off the immune system T cells. Immune checkpoint proteins/receptors include CTLA-4 (Cytotoxic T-Lymphocyte Antigen 4, also known as CD152) and PD-1(Programmed cell Death 1). Checkpoint inhibitors unleash the T cells resulting in T cell proliferation, activation, and a therapeutic response. OPDIVO® is a fully human, immunoglobulin G4 monoclonal antibody that binds to the PD-1 receptor and blocks its interaction with PD-L1 and PD-L2, thereby undoing PD-1 pathway-mediated inhibition of the immune response and unleashing the T cells. YERVOY® is a fully human immunoglobulin G1 monoclonal antibody that blocks Immune checkpoint protein/receptor CTLA-4.Unleashing-T-Cell-Function-with-Combination-Immunotherapy

In the CheckMate-227, Part 1, Phase III trial, a combination of OPDIVO® plus YERVOY® significantly improved Overall Survival (OS), Progression Free Survival (PFS), Objective Response Rates (ORR) and Duration of Response, compared to chemotherapy, independent of PD-L1 expression level. The authors in this study hypothesized that a limited course of chemotherapy combined with OPDIVO® plus YERVOY® could provide rapid disease control, while building on the durable Overall Survival benefit seen with dual PD-1 and CTLA-4 inhibition.

CheckMate-9LA is a randomized, open-label, multi-center, Phase III trial which evaluated the benefit of a combination of OPDIVO® plus YERVOY®, and 2 cycles of Platinum-doublet chemotherapy versus Platinum-doublet chemotherapy for 4 cycles followed by optional Pemetrexed maintenance therapy, as a first-line treatment in patients with metastatic or recurrent NSCLC, regardless of PD-L1 status and histology. In this study, 719 adults treatment naïve patients with histologically confirmed Stage IV/recurrent NSCLC, with ECOG Performance Status 0-1, and no known sensitizing EGFR/ALK alterations, were randomly assigned 1:1 to receive OPDIVO® 360 mg every 3 weeks plus YERVOY® 1 mg/kg every 6 weeks and 2 cycles of platinum-doublet chemotherapy (N=361), or 4 cycles of platinum-doublet chemotherapy alone (N=358). Chemotherapy was based on histology. Patients with non-squamous NSCLC in the chemo-only randomized group could receive optional Pemetrexed maintenance treatment. Patients were treated with immunotherapy until disease progression, unacceptable toxicity, or for 2 years. Patients were stratified by PD-L1 status (less than 1% versus 1% or more), sex, and histology (squamous versus non-squamous). Demographics in treatment groups were well balanced. The Primary end point was Overall Survival (OS). Secondary endpoints included Progression Free Survival (PFS), Objective Response Rate (ORR) and efficacy by PD-L1 subgroups.

At a preplanned interim analysis after a minimum follow up 8.1 months, this trial demonstrated a statistically significant benefit in OS for patients treated with OPDIVO® plus YERVOY® and limited chemotherapy, compared to those who received chemotherapy alone. The median OS was 14.1 months versus 10.7 months, respectively (HR=0.69; P=0.0006). With longer follow up at 12.7 months, this OS benefit continued to improve in the immunotherapy plus chemotherapy group, with a median OS of 15.6 months versus 10.9 months, respectively (HR=0.66). The 1-year OS rates were 63% versus 47%. This clinical benefit was consistent across all efficacy measures in key subgroups including by PD-L1 and histology.

The median PFS was 6.8 months in the OPDIVO® plus YERVOY® and chemotherapy group and 5 months in the chemotherapy-only group (HR=0.70; P=0.0001). The ORR was 38% and 25%, respectively (P= .0003). The median response duration was 10 months in the OPDIVO® plus YERVOY® and chemotherapy group, and 5.1 months in the chemotherapy-only group. Grade 3-4 treatment related Adverse Events were reported in 47% of the patients receiving the immunotherapy plus chemotherapy combination versus 38% in the chemotherapy-only group.

It was concluded that CheckMate 9LA met its Primary endpoint of Overall Survival, and OPDIVO® plus YERVOY® with a limited course of chemotherapy should be considered as a new first line treatment option for patients advanced Non Small Cell Lung Cancer.

Nivolumab (NIVO) + ipilimumab (IPI) + 2 cycles of platinum-doublet chemotherapy (chemo) vs 4 cycles chemo as first-line (1L) treatment (tx) for stage IV/recurrent non-small cell lung cancer (NSCLC): CheckMate 9LA. Reck M, Ciuleanu T-E, Dols MC, et al. J Clin Oncol 38: 2020 (suppl; abstr 9501)

Late Breaking Abstract – ASCO 2020: Local Therapy Does Not Extend Survival in Newly Diagnosed Metastatic Breast Cancer

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SUMMARY: Breast cancer is the most common cancer among women in the US and about 1 in 8 women (13%) will develop invasive breast cancer during their lifetime. Approximately 276,480 new cases of invasive female breast cancer will be diagnosed in 2020 and about 42,170 women will die of the disease. Approximately 6% of newly diagnosed breast cancer patients present with Stage IV disease. Breast surgery is often not a consideration for patients with metastatic breast cancer. However, breast surgery can be offered for palliation of symptoms, taking into consideration the risks and benefits of such intervention, in a patient with an ulcerated, bleeding, or a fungating tumor mass, that cannot be controlled with systemic therapy. It has been hypothesized based on retrospective analyses, that the addition of surgical resection of the primary tumor in the breast, to systemic therapy, in patients presenting with Stage IV disease, improved survival. Randomized clinical trials however have provided conflicting results.

E2108 is a randomized, Phase III trial which evaluated the benefit of locoregional treatment for the intact primary breast tumor, following initial systemic therapy, in newly diagnosed breast cancer patients presenting with Stage IV disease. In this study, 256 eligible patients with de novo metastatic disease, who did not progress during a 4-8 months period, while on optimal systemic therapy based on patient and tumor characteristics, were randomized to either continue systemic therapy alone (N=131) or combine it with locoregional therapy such as surgery and radiation for the intact primary breast tumor (N = 125). Of the 125 patients who received early locoregional therapy, 109 patients underwent surgery of whom 87 had free margins and 74 patients received locoregional radiation therapy. The Primary endpoint was Overall Survival (OS), and Secondary endpoint was locoregional disease control.

At a median follow up of 59 months, there was no significant difference in Overall Survival (OS) between the optimal systemic therapy plus locoregional therapy compared with optimal systemic therapy alone (3-year OS rate was 68.4% versus 67.9%; HR=1.09; P=0.63). Further, the addition of locoregional therapy to systemic therapy, also failed to improve 3-year Progression Free Survival (P=0.40). There was however significantly higher locoregional recurrence or progression in the systemic therapy alone group compared with the systemic therapy plus locoregional therapy group (3-year rate 25.6% versus 10.2%, P=0.003). Health-related Quality of Life measures such as depression, anxiety and well-being were significantly worse in patients who underwent systemic therapy plus locoregional therapy, compared with systemic therapy alone.

The authors concluded that for patients with a new diagnosis of breast cancer presenting with Stage IV disease, surgery and radiation for the primary breast tumor should not be offered, with the expectation of a survival benefit.

A randomized phase III trial of systemic therapy plus early local therapy versus systemic therapy alone in women with de novo stage IV breast cancer: a trial of the ECOG-ACRIN Research Group (E2108). Khan SA, Zhao F, Solin LJ, et al. J Clin Oncol 38: 2020 (suppl; abstr LBA2)

Late Breaking Abstract – ASCO 2020: FDA Approves BAVENCIO® for Maintenance Treatment in Advanced Urothelial Carcinoma

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SUMMARY: The FDA on June 30, 2020 approved BAVENCIO® for maintenance treatment of patients with locally advanced or metastatic Urothelial Carcinoma (UC) that has not progressed with first-line platinum-containing chemotherapy. The American Cancer Society estimates that for 2020, about 81,400 new cases of bladder cancer will be diagnosed in the US and about 17,980 patients will die of the disease. Bladder cancer is the fourth most common cancer in men, but is less common in women, and the average age at the time of diagnosis is 73. Patients with advanced Urothelial Carcinoma are currently treated in the first line setting with a Platinum based chemotherapy regimen. Progression Free Survival (PFS) and Overall Survival (OS) however are generally short because of resistance to chemotherapy. Treatment options for patients who progress after Platinum based chemotherapy are limited, with poor outcomes. The response rates with standard chemotherapy in this patient population, is about 10%.

BAVENCIO® (Avelumab) is a human, immunoglobulin G1 lambda, PD-L1 targeted monoclonal antibody that binds to PD-L1 and blocks the interaction between PD-L1 and its receptor PD-1. This in turn negates the inhibitory effects of PD-L1 on the immune response by unleashing the immune system and restoring antitumor immune responses. In addition, BAVENCIO® induces Antibody Dependent Cell-mediated Cytotoxicity (ADCC). BAVENCIO® was previously granted an accelerated approval by the FDA in 2017 for the treatment of patients with locally advanced or metastatic Urothelial Carcinoma who have disease progression during or following Platinum-containing chemotherapy.

JAVELIN Bladder 100 study is an international, multicenter, open-label, parallel-arm, randomized Phase III trial, which evaluated BAVENCIO® as maintenance therapy following response or stable disease with first-line Platinum-based chemotherapy, in patients with advanced Urothelial Carcinoma. This study included 700 patients with unresectable locally advanced or metastatic Urothelial Cancer, whose disease did not progress following 4 to 6 cycles of standard Gemcitabine with either Cisplatin or Carboplatin. These patients were randomly assigned 1:1 to receive maintenance BAVENCIO® 10 mg/kg IV every 2 weeks in 4 week cycles plus Best Supportive Care (N=350) or BSC alone (N=350). Best Supportive Care included symptom control and pain management, supportive nutrition, correction of metabolic disorders and antibiotics if indicated. Patients were stratified by best response to first-line chemotherapy (Complete vs Partial Response vs stable disease), and by visceral vs non-visceral disease, when initiating first-line chemotherapy. Across the study population, 51% of patients had tumors that were PD-L1 positive. The Coprimary end points were Overall Survival (OS) in all randomized patients, and in those with PD-L1 positive tumors. Secondary end points included Progression Free Survival (PFS), Objective Response Rate (ORR), and safety. The median follow up was 19.6 months for the BAVENCIO® cohort and 19.2 months for the BSC-alone cohort.

The combination of BAVENCIO® plus BSC significantly prolonged OS, compared with BSC alone, in all randomized patients (HR=0.69; P=0.0005), suggesting a 31% reduction in the risk of death with the addition of  maintenance BAVENCIO®. The median OS was 21.4 months with BAVENCIO® plus BSC compared with 14.3 months with BSC alone. Significantly prolonged OS with BAVENCIO® plus BSC, compared with BSC alone, was also noted among patients with PD-L1 positive tumors, and the median OS was not reached in the BAVENCIO® group versus 17.1 months in the control group (HR=0.56; P=0.0003). The OS benefit with BAVENCIO® was noted across all prespecified subgroups, including those defined by Cisplatin-based or Carboplatin-based chemotherapy, and regardless of whether response or stable disease was reached after first-line induction chemotherapy. Based on blinded Independent Central Review, the median PFS favored the BAVENCIO® group both in the overall randomized population (3.7 months versus 2 months, HR=0.62; P<0.001) as well as in the PD-L1 positive subgroup (HR=0.56). All-grade Adverse Events occurred in 98% of the BAVENCIO® group versus 77.7% of the control group, and grade 3/4 AEs occurred in 47.4% versus 25.2%, respectively.

It was concluded that this study met its primary objective, demonstrating significantly prolonged Overall Survival with first-line maintenance BAVENCIO® plus BSC compared with BSC alone, in all patients with advanced Urothelial Carcinoma, and should therefore be the new first-line standard of care in this patient group.

Maintenance avelumab + best supportive care (BSC) versus BSC alone after platinum-based first-line (1L) chemotherapy in advanced urothelial carcinoma (UC): JAVELIN Bladder 100 phase III interim analysis. Powles T, Park SH, Voog E, et al. J Clin Oncol 38: 2020 (suppl; abstr LBA1)

Late Breaking Abstract – ASCO 2020: Adjuvant Therapy with TAGRISSO® Improves Survival in Early Stage EGFR-Mutated Non Small Cell Lung Cancer

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SUMMARY: Lung cancer is the second most common cancer in both men and women and accounts for about 14% of all new cancers and 27% of all cancer deaths. The American Cancer Society estimates that for 2020, about 228, 820 new cases of lung cancer will be diagnosed and 135,720 patients will die of the disease. Lung cancer is the leading cause of cancer-related mortality in the United States. Non-Small Cell Lung Cancer (NSCLC) accounts for approximately 85% of all lung cancers. Of the three main subtypes of NSCLC, 30% are Squamous Cell Carcinomas (SCC), 40% are Adenocarcinomas and 10% are Large Cell Carcinomas. With changes in the cigarette composition and decline in tobacco consumption over the past several decades, Adenocarcinoma now is the most frequent histologic subtype of lung cancer.

Approximately 10-15% of Caucasian patients and 35-50% of Asian patients with Adenocarcinomas, harbor activating EGFR (Epidermal Growth Factor Receptor) mutations and 90% of these mutations are either Exon 19 deletions or L858R substitution mutation in Exon 21. Approximately 25% of patients with EGFR mutated NSCLC have brain metastases at diagnosis, increasing to approximately 40% within two years of diagnosis. The presence of brain metastases often reduces median survival to less than eight months. EGFR-Tyrosine Kinase Inhibitors (TKIs) such as TARCEVA® (Erlotinib), IRESSA® (Gefitinib) and GILOTRIF® (Afatinib), have demonstrated a 60-70% response rate as monotherapy when administered as first line treatment, in patients with metastatic NSCLC, who harbor the sensitizing EGFR mutations. However, majority of these patients experience disease progression within 9-14 months. This resistance to frontline EGFR TKI therapy has been attributed to the most common, acquired T790M “gatekeeper” point mutation in EGFR, identified in 50-60% of patients.EGFR-Tyrosine-Kinase-Inhibitors

TAGRISSO® (Osimertinib) is a highly selective third-generation Epidermal Growth Factor Receptor (EGFR) TKI presently approved by the FDA, for the first-line treatment of patients with metastatic NSCLC, whose tumors have Exon 19 deletions or Exon 21 L858R mutations, as well as treatment of patients with metastatic EGFR T790M mutation-positive NSCLC, whose disease has progressed on or after EGFR-TKI therapy. Further, TAGRISSO® has higher CNS penetration and is therefore able to induce responses in 70-90% of patients with brain metastases. Among patients with metastatic, EGFR-mutant NSCLC, first-line treatment with TAGRISSO® significantly improved median Overall Survival, compared with TARCEVA® and IRESSA®, and should therefore be considered the preferred regimen.

Surgical resection is the primary treatment for approximately 30% of patients with NSCLC who present with early Stage (I–IIIA) disease. These patients are often treated with Cisplatin-based adjuvant chemotherapy to decrease the risk of recurrence. Nonetheless, 45-75% of these patients develop recurrent disease. There is therefore an unmet need for this patient population.

ADAURA is a global, double-blind, randomized Phase III study, which assessed the efficacy and safety of TAGRISSO® versus placebo in patients with Stage IB–IIIA EGFR mutated NSCLC, after complete tumor resection and adjuvant chemotherapy, when indicated. In this study, 682 patients with completely resected Stage IB, II, IIIA NSCLC, with or without postoperative adjuvant chemotherapy, were randomly assigned 1:1 to receive either TAGRISSO® 80 mg orally once daily (N=339) or placebo (N=343) once daily, for up to 3 years. Eligible patients had an ECOG Performance Status of 0 or 1, with confirmed EGFR mutations (Exon 19del or L858R). Treatment groups were well balanced and patients were stratified by Stage (IB/II/IIIA), mutation type (Exon 19del/L858R), and race (Asian/non-Asian). The Primary endpoint was Disease Free Survival (DFS) in Stage II–IIIA patients. Secondary endpoints included Overall Survival (OS) and safety. Following Independent Data Monitoring Committee recommendation, the trial was unblinded early, due to efficacy. The authors reported the results from the unplanned interim analysis.

It was noted that in the patients with Stage II/IIIA disease, the DFS had not been reached with TAGRISSO® versus 20.4 months with placebo (HR=0.17; P<0.0001). The 2-year DFS rate in this patient group with TAGRISSO® was 90% versus 44% with placebo. In the overall population, the DFS was still not reached with TAGRISSO® versus 28.1 months with placebo (HR=0.21; P<0.0001). The 2-year DFS rate in the overall population was 89% with TAGRISSO® versus 53% with placebo. The OS data are still early and immature, and the median OS has not yet been reached in either treatment groups. The safety profile was consistent with the known safety profile of TAGRISSO®.

The authors concluded that adjuvant TAGRISSO® is the first targeted agent in a global randomized trial, to show a statistically significant and clinically meaningful improvement in Disease Free Survival, among patients with Stage IB/II/IIIA EGFR mutation-positive NSCLC, and provides an effective new treatment strategy for this patient group.

Osimertinib as adjuvant therapy in patients (pts) with stage IB–IIIA EGFR mutation positive (EGFRm) NSCLC after complete tumor resection: ADAURA. Herbst RS, Tsuboi M, John T, et al. J Clin Oncol 38: 2020 (suppl; abstr LBA5)

KEYTRUDA® Superior to ADCETRIS® in Relapsed or Refractory Classical Hodgkin Lymphoma

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SUMMARY: The American Cancer Society estimates that in the United States for 2020, about 8,480 new cases of Hodgkin Lymphoma will be diagnosed and about 970 patients will die of the disease. Hodgkin Lymphoma is classified into two main groups – Classical Hodgkin Lymphomas and Nodular Lymphocyte Predominant type, by the World Health Organization. The Classical Hodgkin Lymphomas include Nodular sclerosing, Mixed cellularity, Lymphocyte rich, Lymphocyte depleted subtypes and accounts for approximately 10% of all malignant lymphomas. Nodular sclerosis Hodgkin Lymphoma histology, accounts for approximately 80% of Hodgkin lymphoma cases in older children and adolescents in the United States. Classical Hodgkin Lymphoma is a malignancy of primarily B lymphocytes and is characterized by the presence of large mononucleated Hodgkin (H) and giant multinucleated Reed-Sternberg (RS) cells, collectively known as Hodgkin and Reed-Sternberg cells (HRS).The HRS cells in turn recruit an abundance of ineffective inflammatory cells and infiltrates of immune cells.WHO-Classification-of-Hodgkin-Lymphoma

Preclinical studies suggest that HRS cells evade immune detection by exploiting the pathways associated with immune checkpoint, Programmed Death-1 (PD-1) and its ligands PD-L. Classical Hodgkin Lymphoma is an excellent example of how the tumor microenvironment influences cancer cells to proliferate and survive. The most common genetic abnormality in Nodular sclerosis subtype of Hodgkin lymphoma is the selective amplification of genes on the short arm of chromosome 9 (9p24.1) which includes JAK-2, with resulting increased expression of PD-1 ligands such as PDL1 and PDL2 on HRS cells, as well as increased JAK-STAT activity, essential for the proliferation and survival of Hodgkin Reed-Sternberg (HRS) cells. Infection with Epstein–Barr virus (EBV) similarly can increase the expression of PDL1 and PDL2 in EBV-positive Hodgkin lymphomas. It would therefore seem logical to block or inhibit immune check point PD-1 rather than both its ligands, PDL1 and PDL2.

Immune checkpoints are cell surface inhibitory proteins/receptors that are expressed on activated T cells. They harness the immune system and prevent uncontrolled immune reactions. KEYTRUDA® is a fully humanized, Immunoglobulin G4, anti-PD-1, monoclonal antibody, that binds to the PD-1 receptor and blocks its interaction with ligands PD-L1 and PD-L2, thereby undoing PD-1 pathway-mediated inhibition of the immune response and unleashing the tumor-specific effector T cells. ADCETRIS® (Brentuximab vedotin) is an Antibody-Drug Conjugate (ADC) that targets CD30, which is a surface antigen, expressed on Reed-Sternberg cells, in patients with Classical Hodgkin Lymphoma. This ADC consists of an anti-CD30 monoclonal antibody linked to MonoMethyl Auristatin E (MMAE), an antimicrotubule agent. Upon binding to the CD30 molecule on the cancer cells, MMAE is released into the cancer cell, resulting in cell death.

Patients with Relapsed or Refractory Classical Hodgkin Lymphoma (R/R cHL) are often treated with salvage chemotherapy and Autologous Stem Cell Transplant (ASCT). There are however no standard interventions for patients ineligible for ASCT due to chemo-refractory disease, comorbidity, or advanced stage. PD-1 inhibitor such as KEYTRUDA® as well as ADCETRIS® has shown antitumor activity in R/R cHL.

KEYNOTE-204 is a randomized, international, open-label, Phase III study in which KEYTRUDA® was compared with ADCETRIS® among patients with Relapsed or Refractory Classical Hodgkin Lymphoma (R/R cHL). In this study, 304 patients were randomized 1:1, and 300 patients were treated and assigned to receive KEYTRUDA® 200 mg IV every 3 weeks (N=148) or ADCETRIS® 1.8 mg/kg IV every 3 weeks (N=152). Enrolled patients were post-Autologous Stem Cell Transplant (ASCT) or ineligible for ASCT, had measurable disease and had an ECOG Performance Status of 0 or 1. Both ADCETRIS®-naive and ADCETRIS®-exposed patients were eligible. Patients were stratified by prior ASCT and status after first-line therapy (primary refractory versus relapsed less than 12 months versus relapsed 12 months or more after end of first-line therapy). The Primary endpoints were Progression Free Survival (PFS) per Blinded Independent Central Review (BICR) and Overall Survival (OS). Secondary endpoints included PFS per investigator review, Objective Response Rate (ORR), and Safety. Median follow up was 24.7 months.

The median PFS was 13.2 months in the KEYTRUDA® group compared with 8.3 months in the ADCETRIS® group (HR=0.65, P=0.00271), suggesting an increase in PFS of 4.9 months with KEYTRUDA®. This benefit with KEYTRUDA® was observed in all subgroups tested, including those ineligible for ASCT (HR=0.61), those with primary refractory disease (HR=0.52), those who were ADCETRIS® naïve (HR=0.67), as well as those who received prior treatment with ADCETRIS® (HR=0.34). The ORR was 65.6% versus 54.2%, and the median Duration of Response was 20.7 months versus 13.8 months, in the KEYTRUDA® and ADCETRIS® groups respectively. Treatment Related Adverse Events were similar in both treatment groups and Grade 3-5 toxicities occurred in 19.6% of patients treated with KEYTRUDA® and 25% of patients treated with ADCETRIS®.

It was concluded that among patients with Relapsed/Refractory Classical Hodgkin Lymphoma, KEYTRUDA® was superior to ADCETRIS®, with a statistically significant and clinically meaningful improvement in PFS across all subgroups tested, and with safety consistent with previous reports. The authors added that KEYTRUDA® should be considered the preferred treatment option and the new standard of care in this patient population.

KEYNOTE-204: Randomized, open-label, phase III study of pembrolizumab (pembro) versus brentuximab vedotin (BV) in relapsed or refractory classic Hodgkin lymphoma (R/R cHL). Kuruvilla J, Ramchandren R, Santoro A, et al. Presented at: 2020 ASCO Virtual Scientific Program; May 29, 2020. J Clin Oncol 38: 2020 (suppl; abstr 8005).