Author: RR

Final Analysis Confirms Superior OS Benefit with ERLEADA® in Metastatic Castrate Sensitive Prostate Cancer

RR

SUMMARY: Prostate cancer is the most common cancer in American men with the exclusion of skin cancer, and 1 in 8 men will be diagnosed with prostate cancer during their lifetime. It is estimated that in the United States, about 248,530 new cases of prostate cancer will be diagnosed in 2021 and 34,130 men will die of the disease. The development and progression of prostate cancer is driven by androgens. Androgen Deprivation Therapy (ADT) or testosterone suppression has therefore been the cornerstone of treatment of advanced prostate cancer, and is the first treatment intervention. Androgen Deprivation Therapies have included bilateral orchiectomy or Gonadotropin Releasing Hormone (GnRH) analogues, with or without first generation Androgen Receptor (AR) inhibitors such as CASODEX® (Bicalutamide), NILANDRON® (Nilutamide) and EULEXIN® (Flutamide) or with second generation anti-androgen agents, which include ZYTIGA® (Abiraterone), XTANDI® (Enzalutamide), ERLEADA® (Apalutamide) and NUBEQA® (Darolutamide). Approximately 10-20% of patients with advanced Prostate cancer will progress to Castration Resistant Prostate Cancer (CRPC) within five years during ADT, and over 80% of these patients will have metastatic disease at the time of CRPC diagnosis.

ERLEADA® (Apalutamide) is an orally administered Androgen Receptor (AR) inhibitor that binds directly to the ligand-binding domain of the AR. ERLEADA® inhibits AR nuclear translocation, inhibits DNA binding, and impedes AR-mediated transcription. ERLEADA® is presently approved for the treatment of patients with metastatic Castration Sensitive Prostate Cancer (CSPC) and non-metastatic Castration Resistant Prostate Cancer (CRPC).

TITAN (Targeted Investigational Treatment Analysis of Novel Anti-androgen) is an international, randomized, placebo-controlled, double-blind, Phase III trial, conducted to determine whether treatment with ERLEADA® would result in longer radiographic Progression Free Survival (PFS) and Overall Survival (OS) than placebo, with an acceptable Safety profile and Health-Related Quality of Life, among patients with metastatic CSPC, who were receiving concomitant ADT. In this study a 1052 patients were randomly assigned 1:1 to receive ERLEADA® plus ADT (N=525) or placebo plus ADT (N=527). Patients received ERLEADA® 240 mg orally once daily, in addition to continuous ADT. The median age was 68 years and eligible patients had adenocarcinoma of the prostate with distant metastatic disease and were castration sensitive (patients were not receiving ADT at the time of disease progression). Previous treatment for prostate cancer was limited to no more than 6 cycles of Docetaxel, with no evidence of progression during treatment. A total of 16% of the patients had undergone prostatectomy or received radiotherapy for localized disease, and 11% had received previous Docetaxel therapy and 63% had high-volume disease. The co-Primary end points were OS and radiographic PFS (rPFS).

At the first interim analysis, with a median follow up of 22.7 months, ERLEADA® significantly improved dual Primary end points of OS (HR for death=0.67; P=0.005) and rPFS (HR for radiologic progression or death=0.48; P<0.001; Chi et al. NEJM. 2019). When this data was reported, OS information was from the first planned interim analysis, whereas rPFS data was final. TITAN study was then unblinded, allowing patients without progression who were still receiving placebo, to cross over to ERLEADA®. The authors in this publication reported the final analysis of efficacy and safety results from TITAN study.

At a median follow up was 44.0 months, the previous efficacy data was confirmed even after 39.5% of patients in the placebo group crossed over to receive ERLEADA®. Median treatment durations were 39.3 months with ERLEADA® in the ERLEADA® group, 20.2 months with placebo in the placebo group, and 15.4 months with ERLEADA® in placebo-treated patients who crossed over. In the intention-to-treat population, including patients who crossed over from the placebo group, the median Overall Survival was Not Reached in the ERLEADA® group versus 52.2 months in the placebo group (HR=0.65, P < 0.0001). The OS was superior in the ERLEADA® group compared with the placebo group despite crossover and the 4-year survival rates were 65% with ERLEADA® versus 52% with placebo. When the analysis was adjusted for crossover, the Hazard Ratio further improved to 0.52 (P<0.0001). At final analysis, cytotoxic chemotherapy had been initiated in 13.1% of ERLEADA®-treated patients versus 23.9% of placebo-treated patients (HR=0.47, P<0.0001). Secondary endpoints including second PFS (PFS2) was also in favor of ERLEADA®, and Health-Related Quality of Life (HRQoL) was maintained in the ERLEADA® group throughout the study and was not different from the placebo group. Safety was consistent with previous reports.

The authors concluded that with close to 4 years of follow up, the final analysis of the TITAN study demonstrated that among patients with metastatic Castrate Sensitive Prostate Cancer, ERLEADA® plus ADT provided an improvement in Overall Survival with a 35% reduction in risk of death, which further increased to 48% reduction, after adjusting for patients who had crossed over from placebo to ERLEADA®. Further, ERLEADA® also delayed castration resistance, and maintained Quality of Life.

Apalutamide in Patients with Metastatic Castration-Sensitive Prostate Cancer: Final Survival Analysis of the Randomized, Double-Blind, Phase III TITAN Study. Chi KN, Chowdhury S, Bjartell A, et al. J Clin Oncol. 2021 Apr 29;JCO2003488. doi: 10.1200/JCO.20.03488. Online ahead of print.

ZYNLONTA® (Loncastuximab tesirine-lpyl)

RR

The FDA on April 23, 2021 granted accelerated approval to ZYNLONTA®, a CD19-directed antibody and alkylating agent conjugate, for adult patients with Relapsed or Refractory Large B-Cell Lymphoma after two or more lines of systemic therapy, including Diffuse Large B-Cell Lymphoma (DLBCL) not otherwise specified, DLBCL arising from Low Grade Lymphoma, and High-Grade B-cell Lymphoma. ZYNLONTA® is a product of ADC Therapeutics SA.

Neoadjuvant Chemotherapy in Locally Advanced Rectal Cancer

RR

SUMMARY: The American Cancer Society estimates that 45,230 new cases of rectal cancer will be diagnosed in the US in 2021. Based on the information from the SEER database, the 5-year relative survival rates for rectal cancer, all SEER stages combined, is 67%. The current standard of care for patients with locally advanced rectal cancer (Stages T3, T4, or N+) consists of Chemoradiation followed by Total Mesorectal Excision (TME), which provides good local disease control, although distant metastases can still occur. Adjuvant chemotherapy after preoperative Chemoradiation remains controversial, as it has not shown an improvement in Overall Survival (OS). This has been attributed in part to poor treatment compliance. Phase II trials of total neoadjuvant therapy have yielded promising results but there is presently no data from Phase III trials.

The Phase III PRODIGE 23 trial sponsored by the French UNICANCER GI group, investigated the role of neoadjuvant modified FOLFIRINOX before standard preoperative chemoradiotherapy, in patients with locally advanced rectal cancer. The aim of the study was to assess whether administering neoadjuvant chemotherapy before preoperative Chemoradiation could reduce the risk of distant recurrences. In this study, 461 patients were randomly assigned 1:1 to either the neoadjuvant chemotherapy group (N=231) or the standard-of-care Chemoradiation group (N=230). Eligible patients had newly diagnosed, biopsy-proven, rectal adenocarcinoma staged cT3 or cT4 M0, with a Performance Status of 0-1. The neoadjuvant chemotherapy group received preoperative chemotherapy with FOLFIRINOX (Oxaliplatin 85 mg/m2 IV, Irinotecan 180 mg/m2 IV, Leucovorin 400 mg/m2 IV, and Fluorouracil 2400 mg/m2 IV as a continuous infusion over 46 hours every 14 days for 6 cycles), followed by Chemoradiation (50 Gy over 5 weeks along with concurrent Capecitabine 800 mg/m2 orally twice daily for 5 days per week), followed by Total Mesorectal Excision, and adjuvant chemotherapy which consisted of modified FOLFOX6 (Oxaliplatin 85 mg/m2 IV and Leucovorin 400 mg/m2 IV, followed by Fluorouracil 400 mg/m2 IV bolus and then Fluorouracil 2400 mg/m2 continuous infusion over 46 hours) every 14 days for six cycles or Capecitabine 1250 mg/m2 orally twice daily on days 1-14 every 21 days.

The Chemoradiotherapy group received preoperative Chemoradiation (50.4 Gy over 5 weeks along with Capecitabine 800 mg/m2 orally twice daily for 5 days per week), followed 7 weeks later by Total Mesorectal Excision and adjuvant chemotherapy, which consisted of 6 months (12 cycles) of modified FOLFOX or 6-8 cycles of Capecitabine. It should be noted that patients received the same schedule of Chemoradiation, the same surgery, and the same total duration of chemotherapy (6 months) in both groups.

The Primary endpoint was Disease Free Survival (DFS) at 3 years. Secondary endpoints included Overall Survival (OS), Metastasis-Free Survival (MFS), and Cancer-Specific Survival (CSS). Safety analyses were performed on treated patients. More than 90% of patients received all planned cycles of FOLFIRINOX.

At a median follow-up of 46.5 months, the 3-year DFS rates were 76% in the neoadjuvant chemotherapy group and 69% in the standard-of-care group (HR=0.69; P=0.034). This represented a 31% reduction in the DFS hazard in the neoadjuvant group. Metastasis-Free-Survival at 3 years was significantly improved in the neoadjuvant group (79% vs 72%, P=0.017) and the pathologic Complete Responses were also significantly higher in the neoadjuvant group (28% versus 12%; P<0.001).
FOLFIRINOX was reported to be well tolerated with 92% compliance rate with this regimen. There were significantly more grade 3 or 4 adverse events in the Chemoradiation group, especially neutropenia and neuropathy. There were significantly more Grade 3 or 4 adverse events associated with adjuvant chemotherapy in the Chemoradiation control group (79% versus 45%, P<0.0001). Grade 3 or 4 neutropenia, thrombocytopenia, lymphopenia and neuropathy, all occurred significantly more often in the patients who received 6 months of adjuvant therapy (Chemoradiation group), suggesting that for the same duration of chemotherapy, the perioperative approach was better tolerated than adjuvant chemotherapy.

The authors concluded that chemotherapy intensification using FOLFIRINOX before preoperative Chemoradiation significantly improved outcomes, with better tolerance and decreased neurotoxicity, compared with standard-of-care preoperative Chemoradiation, among patients with cT3 or cT4 M0 rectal cancer.

Neoadjuvant chemotherapy with FOLFIRINOX and preoperative chemoradiotherapy for patients with locally advanced rectal cancer (UNICANCER-PRODIGE 23): a multicentre, randomised, open-label, phase 3 trial. Conroy T, Bosset J-F, Etienne P-L, et al. Lancet Oncol. 2021;22:702-715.

Somatic Tumor Mutations and Risk for Thrombosis

RR

SUMMARY: The Center for Disease Control and Prevention (CDC) estimates that approximately 1-2 per 1000 individuals develop Deep Vein Thrombosis (DVT)/Pulmonary Embolism (PE) each year in the United States, resulting in 60,000-100,000 deaths. Venous ThromboEmbolism (VTE) is the third leading cause of cardiovascular mortality, after myocardial infarction and stroke. Ambulatory cancer patients initiating chemotherapy are at varying risk for Venous Thromboembolism (VTE), which in turn can have a substantial effect on health care costs, with negative impact on quality of life.

Approximately 20% of cancer patients develop VTE and about 20% of all VTE cases occur in patients with cancer. Cancer patients have a 4-7 fold increased risk of thrombosis, compared with those without cancer, and patients with cancer and VTE are at a markedly increased risk for morbidity and mortality. The high risk of recurrent VTE, as well as bleeding in this patient group, makes anticoagulant treatment challenging.

The etiology of thrombosis in cancer is multifactorial, and the vascular system is an important interface between the malignant cells and their systemic and external environments. Genetic alterations in malignant cells, as they respond to their microenvironment, can result in inflammation, angiogenesis, and tissue repair. This in turn leads to the local and systemic activation of the coagulation system. It has been postulated that the procoagulant effect of malignant cells may be related to the release of soluble mediators such as G-CSF into the circulation or by the shedding of procoagulant Extracellular Vesicles (EVs) harboring Tissue Factor. Previously published studies had entertained the notion that certain oncogenic mutations may deregulate hemostatic genes (coagulome) in cancer cells.

The researchers conducted this study to assess potential associations between tumor molecular signatures and Cancer Associated Thrombosis, including tumor-specific mutations, and the presence of Clonal Hematopoiesis. The authors analyzed deep-coverage targeted DNA-sequencing data of more than 14,000 solid tumor samples from 11,695 patients, using the Memorial Sloan Kettering-Integrated Mutation Profiling of Actionable Cancer Targets platform, to identify somatic alterations associated with Venous ThromboEmbolism (VTE). Among the patients included, more than 15 different solid tumor types were represented and 72% had metastatic disease at time of analysis.
Among these patients, there were 693 episodes of Cancer Associated Thrombosis, and the authors in addition to looking for associations with standard clinical variables such as diagnosis, stage and therapy, also assessed potential linkage of Cancer Associated Thrombosis with oncogenic mutations. The Primary endpoint was defined as the first instance of cancer-associated Pulmonary Embolism and/or proximal/distal lower extremity Deep Vein Thrombosis.

It was noted that several genes were found to be significantly associated with the VTE risk, regardless of tumor type. Independent of tumor type, the following mutations were associated with increased risk of Cancer Associated Thrombosis: KRAS (HR=1.34 suggesting 1.34 times higher risk), STK11 (HR=2.12), KEAP1 (HR=1.84), CTNNB1 (HR=1.73), CDKN2B (HR=1.45) and MET (HR=1.83). Mutations in SETD2 were associated with a decreased risk of Cancer Associated Thrombosis (HR=0.35). Clonal Hematopoiesis (CH) is an aging associated biologic state, with genetic mutations occurring in the background of active malignancies. The presence of Clonal Hematopoiesis was not associated with an increased risk of Cancer Associated Thrombosis.

The authors from this study concluded that this is the first large-scale study to explore the link between cancer genomics and thrombosis. Somatic tumor mutations of STK11, KRAS, CTNNB1, KEAP1, CDKN2B, and MET were associated with an increased risk of VTE in patients with solid tumors. It remains unclear whether drugs targeting these genetic alterations would alter the course of Cancer Associated Thrombosis.

Genomic profiling identifies somatic mutations predicting thromboembolic risk in patients with solid tumors. Dunbar A, Bolton KL, Devlin SM, et al. Blood 2021;137:2103-2113.