Use of Adjuvant Bisphosphonates and Other Bone-Modifying Agents in Breast Cancer A Cancer Care Ontario and American Society of Clinical Oncology Clinical Practice Guideline

SUMMARY: Breast cancer is the most common cancer among women in the US and about 1 in 8 women (12%) will develop breast cancer during their life time. Approximately, 255,180 new cases of breast cancer will be diagnosed in 2017 and 41,070 women will die of the disease. Cancer Care Ontario and ASCO convened a Working Group and Expert Panel and following a systematic review of the literature, developed evidence-based recommendations regarding the use of bisphosphonates and other bone-modifying agents, as adjuvant therapy, for patients with breast cancer. These guidelines are based on several important findings noted in previously published studies and in the more recently published Oxford Overview (Early Breast Cancer Trialists’ Collaborative Group) analysis of individual patient data.

1) Adjuvant bisphosphonates were found to reduce bone recurrence and improve survival in postmenopausal patients with non-metastatic breast cancer (including those with natural menopause or menopause induced by ovarian suppression or ablation)

2) The absolute benefit with adjuvant bisphosphonates was greater in patients who were at a higher risk of recurrence, and almost all clinical trials were conducted in patients who also received systemic therapy.

3) Most studies evaluated ZOMETA® (Zoledronic acid) or BONEFOS® (Clodronate), and there was extremely limited data for other bisphosphonates. Although XGEVA® (Denosumab) was found to reduce fractures, long-term survival data is awaited.

The following is a summary of the panel’s recommendations:

Recommendation 1

a) Administration of bisphosphonates as adjuvant therapy should be considered for postmenopausal patients with breast cancer (including patients who are premenopausal before treatment and have menopause induced by ovarian suppression as detailed in Recommendation 5) deemed candidates for adjuvant systemic therapy.

b) The final decision of whether or not to administer bisphosphonates should be made during consultation between the patient and oncologist, taking into account patient and disease characteristics, including the risk of recurrence, and weighing the potential benefits and risks.

Recommendation 2

a) Zoledronic acid and Clodronate are the recommended bisphosphonates for adjuvant therapy in breast cancer.

b) There is a need for more information comparing different agents and schedules, and it is recommended that such trials be conducted to establish the utility and optimal administration of other bisphosphonates for adjuvant therapy.

Recommendation 3

a) There is insufficient evidence at this time to make any recommendation regarding the use of Denosumab in the adjuvant setting.

b) It is recommended that studies directly comparing Denosumab with bisphosphonates and evaluating administration schedules, be conducted.

Recommendation 4

a) For patients who will receive adjuvant bisphosphonates (Recommendation 1), Zoledronic acid 4 mg IV over 15 minutes (or longer) every 6 months for 3 to 5 years or Clodronate PO 1,600 mg daily for 2 to 3 years is recommended. Different durations may be considered.

b) More research is recommended comparing different bone-modifying agents, doses, dosing intervals, and durations.

Recommendation 5

For purposes of adjuvant bisphosphonate use, the definition of menopause should include natural menopause (at least 12 months of amenorrhea prior to initiation of chemotherapy or endocrine therapy) and menopause induced by ovarian ablation or suppression (but not the cessation of menses due to chemotherapy alone). In women aged 60 years or less with a previous hysterectomy and ovaries left in place, Luteinizing Hormone, Follicle Stimulating Hormone and Serum Estradiol should be in the postmenopausal range and measured prior to initiation of any systemic therapy, to receive adjuvant bisphosphonates.

Recommendation 6

a) A dental assessment is recommended prior to commencement of bisphosphonates, where feasible, and any pending dental or oral health problems should be dealt with prior to starting treatment, if possible. Patients should be informed of the risk of developing osteonecrosis of the jaw, especially with tooth extractions and other invasive dental procedures. Patients should inform their dental practitioner of their treatment. Patients with suspected osteonecrosis of the jaw should be referred to a dental practitioner with expertise in treating this condition. Recent guidelines or position papers by groups such as the International Task Force on Osteonecrosis of the Jaw, the American Association of Oral and Maxillofacial Surgeons, and the American Dental Association should be consulted.

b) Patients should have Serum Calcium measured prior to starting treatment. Patients receiving intravenous bisphosphonates (Zoledronic acid) should be monitored for renal function, prior to starting this treatment and for Serum Calcium and increase in Serum Creatinine, throughout the treatment period.

c) Calcium and vitamin D supplementation is recommended unless otherwise contraindicated. Oral bisphosphonates and Calcium should not be taken concurrently. Several monographs suggest an interval of at least 2 hours to allow for maximum absorption.

d) Symptoms such as ocular pain or loss of vision may be due to serious inflammatory conditions such as uveitis or scleritis and should be promptly evaluated by an ophthalmologist.

Use of Adjuvant Bisphosphonates and Other Bone-Modifying Agents in Breast Cancer: A Cancer Care Ontario and American Society of Clinical Oncology Clinical Practice Guideline. Dhesy-Thind S, Fletcher GG, Blanchette PS, et al. DOI: 10.1200/JCO.2016.70.7257 Journal of Clinical Oncology – published online before print March 6, 2017

FDA Approves KISQALI® for First-Line Treatment of Hormone Receptor Positive Advanced Breast cancer

SUMMARY: The FDA on March 13, 2017 approved KISQALI® (Ribociclib), a cyclin-dependent kinase 4/6 inhibitor, in combination with an Aromatase Inhibitor, as initial endocrine-based therapy for the treatment of postmenopausal women with Hormone Receptor (HR)-positive, Human Epidermal growth factor Receptor 2 (HER2)-negative advanced or metastatic breast cancer. Breast cancer is the most common cancer among women in the US and about 1 in 8 women (12%) will develop breast cancer during their life time. Approximately, 255,180 new cases of breast cancer will be diagnosed in 2017 and 41,070 women will die of the disease. Approximately 70% of breast tumors express Estrogen Receptors and/or Progesterone Receptors and these patients are often treated with anti-estrogen therapy as first line treatment. However, resistance to hormonal therapy occurs in a majority of the patients.

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. Cyclin Dependent Kinases 4 and 6 (CDK4 and CDK6), 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.

KISQALI® is an orally bioavailable, selective, small-molecule inhibitor of CDK4/6 that blocks the phosphorylation of RetinoBlastoma protein, thereby preventing cell-cycle progression and inducing G1 phase arrest. In a phase 1b study involving postmenopausal women with ER positive, HER2-negative advanced breast cancer, KISQALI® in combination with FEMARA® (Letrozole) demonstrated an Overall Response Rate (ORR) of 46% and a Clinical Benefit Rate of 79%, in treatment-naïve patients with advanced breast cancer.

MONALEESA-2 trial is a randomized, double-blind, placebo-controlled, phase III study in which 668 patients were randomly assigned in a 1:1 ratio to receive either KISQALI® plus FEMARA® (Letrozole) or placebo plus FEMARA®. Eligible patients included post-menopausal women with HR-positive, HER2-negative advanced or metastatic breast cancer who had received no prior therapy for advanced disease. Treatment consisted of oral KISQALI® 600 mg daily on a 3-weeks on and 1-week off schedule, in 28-day treatment cycles plus FEMARA® 2.5 mg orally daily on a continuous schedule or placebo plus FEMARA®. Patients were stratified according to the presence or absence of liver or lung metastases and treatment was continued until disease progression or unacceptable toxicity. No treatment crossover was allowed. The median age was 62 years and close to 60% of the patients had visceral metastases. The primary end point was Progression Free Survival (PFS) and secondary end points included Overall Survival (OS), Overall Response Rate (ORR), Clinical Benefit Rate (Overall Response plus stable disease lasting 24 weeks or more), safety, and Quality of Life assessments.

A pre-planned interim efficacy analysis demonstrated a significant improvement in the PFS amongst the KISQALI® group compared to the placebo group (HR=0.56; P<0.0001). The median duration of follow-up was 15.3 months. The estimated median PFS had not been reached in the KISQALI® group and was 14.7 months in the placebo containing arm. The Overall Response Rate (ORR) in patients with measurable disease was 52.7% in the KISQALI® group and 37.1% in the placebo plus FEMARA® group (P<0.001). Overall Survival data was mature at the time of this analysis. The rates of discontinuation because of adverse events were 7.5% in the KISQALI® group and 2.1% in the placebo group. The most common adverse reactions observed in patients taking KISQALI® were myelosuppression, nausea, vomiting, diarrhea and fatigue, as well as abnormal liver function tests. KISQALI® has been shown to prolong the QT interval in a dose-dependent manner and prolongation of the QT interval occurred in 3.3% of patients treated at the 600 mg dose, with changes mostly occurring within the first 4 weeks of treatment.

The authors concluded that among patients receiving initial systemic treatment for HR-positive, HER2-negative advanced breast cancer, the addition of KISQALI® to FEMARA® significantly prolonged PFS compared to FEMARA® alone, with a higher rate of myelosuppression noted in the KISQALI® group. Ribociclib as First-Line Therapy for HR-positive, Advanced Breast Cancer. Hortobagyi GN, Stemmer SM, Burris HA, et al. N Engl J Med 375:1738-1748, 2016.

Patients with Lung Cancer and Liver Metastases May Not Benefit from OPDIVO®

SUMMARY: Lung cancer is the second most common cancer in both men and women and accounts for about 13% of all new cancers and 27% of all cancer deaths. The American Cancer Society estimates that for 2017 about 222,500 new cases of lung cancer will be diagnosed and over 155,000 patients will die of the disease. Non Small Cell Lung Cancer accounts for approximately 85% of all lung cancers. The treatment paradigm for malignancies has been rapidly evolving, with a better understanding of the Immune checkpoints or gate keepers. 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. Survival of cancer cells in the human body may be to a significant extent related to their ability to escape immune surveillance, by inhibiting T lymphocyte activation. The T cells of the immune system therefore play a very important role in modulating the immune system. Under normal circumstances, Immune checkpoints or gate keepers inhibit an intense immune response by switching off the T cells of the immune system. With the recognition of Immune checkpoint proteins and their role in suppressing antitumor immunity, antibodies are now available that target the membrane bound inhibitory Immune checkpoint proteins/receptors such as CTLA-4 (Cytotoxic T-Lymphocyte Antigen 4, also known as CD152), PD-1(Programmed cell Death 1), as well as Programmed cell Death Ligands (PD-L1), that are expressed by cells in the tumor micro environment. By targeting the Immune check point proteins or their ligands, T cells are unleashed, resulting in T cell proliferation, activation and a therapeutic response.

OPDIVO® (Nivolumab) 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. Even though immune checkpoint inhibition has taken center stage in the management of advanced lung cancer as well as a number of other malignancies, the efficacy of these agents appears to vary based on the site of metastatic disease. Previously published studies have shown that in patients with advanced NSCLC, adrenal lesions and lymph nodes were more responsive when treated with OPDIVO®, followed by lung lesions. Liver lesions were less responsive to OPDIVO®. (Nishino M, Ramaiya NH, Chambers ES, et al. Immune-related response assessment during PD-1 inhibitor therapy in advanced non-small-cell lung cancer patients. Journal for Immunotherapy of Cancer. 2016;4:84. doi:10.1186/s40425-016-0193-2).

To address this further, the authors in this publication reviewed the efficacy of OPDIVO® in lung cancer patients with hepatic metastases, at their institution. A retrospective study was conducted and this analysis included data from 75 patients with advanced lung cancer, who were treated with PD1 inhibitor OPDIVO®, at East Carolina University. The study was designed to evaluate predictive markers of response to immune checkpoint blockade. Thirteen percent (13%) of the patients had liver metastases. The median age was 62 years, 22% of the patients had squamous cell, 33% had adenocarcinoma, and 44% had small cell neuroendocrine histology. Patients had an average of 1.7 therapies prior to treatment with OPDIVO®. Patients in this study received an average of 4 cycles of anti-PD1 therapy with OPDIVOreg;. Forty four percent (44%) of the patients received adjunctive therapy such as radiation (33%) or immune modulating chemotherapy, with the aim of augmenting the effect of the anti-PD1 therapy.

It was noted that that none of the patients with hepatic metastases experienced an objective decrease in their liver metastases after treatment with OPDIVO®. These patients had an average survival of 132 days after initial treatment with OPDIVO®.

The authors concluded that this is the largest reported series evaluating lung cancer patients with hepatic metastases, who had been treated with PD-1 inhibitors. They noted that consistent with previously published studies, patients with liver metastases have poor outcomes with anti-PD1 therapy and the mechanisms underlying such resistance must be elucidated, so that more effective treatment combinations can be developed. Outcomes with immune checkpoint inhibitor use in lung cancer patients with hepatic metastases. Addepalli S, Chipman R, Stroud G, et al. J Clin Oncol 35, 2017 (suppl 7S; abstract 38)

FDA Approves IMBRUVICA® for Marginal Zone Lymphoma

SUMMARY: The FDA on January 18, 2017 granted accelerated approval to IMBRUVICA® (Ibrutinib) for the treatment of patients with Marginal Zone Lymphoma (MZL), who require systemic therapy and have received at least one prior anti-CD20 based therapy. The American Cancer Society estimates that in 2017, about 72,240 people will be diagnosed with Non Hodgkin Lymphoma (NHL) in the United States and about 20,140 individuals will die of this disease. Indolent Non Hodgkin Lymphomas are mature B-cell lymphoproliferative disorders and include Follicular Lymphomas, Small Lymphocytic Lymphomas (SLL), LymphoPlasmacytic Lymphomas (LPL) and Marginal Zone Lymphoma subtypes such as Nodal Marginal Zone Lymphoma (NMZL), Extranodal Marginal Zone Lymphoma (ENMZL)/Mucosa-Associated Lymphoid Tissue (MALT) lymphoma and Splenic Marginal Zone Lymphoma (SMZL). Marginal Zone Lymphoma is an indolent B-cell lymphoma originating in the lymph nodes as well as in organs including the stomach, salivary glands, thyroid gland, lungs and spleen. It accounts for approximately 10% of all cases of Non Hodgkin Lymphomas (NHL) in adults and is often linked to chronic infection. When treatment is indicated, patients are often treated with a RITUXAN® (Rituximab) based regimens with improved outcomes. Relapses however are common and there is presently no therapy, specifically approved for the treatment of Marginal Zone Lymphoma.

Normal B-cell activation and proliferation is dependent on B-Cell Receptor (BCR) signaling. This signaling is also important for initiation and progression of B-cell lymphoproliferative disorders. Bruton’s Tyrosine Kinase (BTK) is a member of the Tec family of kinases, downstream of the B-cell receptor and is predominantly expressed in B-cells. It is a mediator of B-cell receptor signaling in normal and transformed B-cells. Following binding of antigen to the B-Cell Receptor, kinases such as Syk (Spleen Tyrosine Kinase), Lyn (member of the Src family of protein tyrosine kinases) and BTK (Bruton’s Tyrosine Kinase) are activated, with subsequent propagation through PI3K/Akt, MAPK, and NF-κB pathways. This results in B-cell activation and proliferation. IMBRUVICA® (Ibrutinib) is an oral, irreversible inhibitor of BTK and inhibits cell proliferation and promotes programmed cell death (Apoptosis) by blocking B-cell activation and signaling. IMBRUVICA® is presently approved by the FDA for the treatment of patients with Chronic Lymphocytic Leukemia/ Small Lymphocytic Lymphoma including those with del-17p, patients with Mantle Cell Lymphoma who had received at least one prior therapy, and patients with Waldenstrom’s Macroglobulinemia.

The approval of IMBRUVICA®, in MZL was based on results from a multicenter, open-label, single-arm, phase II trial, in which the safety and efficacy of IMBRUVICA® was evaluated in 63 patients with Marginal Zone Lymphoma. Enrolled patients had previously received one or more prior therapies including at least one anti-CD20 targeted monoclonal antibody -containing regimen or monotherapy RITUXAN®. The subtypes of Marginal Zone Lymphomas included, Extra Nodal MZL (N=32), Nodal MZL (N=17) and Splenic MZL (N=14). The median number of prior systemic therapies was 2 and 35% of the enrolled patients had 3 or more prior therapies. Treatment consisted of IMBRUVICA® 560 mg orally once daily until progression or unacceptable toxicity. The primary study endpoint was Overall Response Rate (ORR). Secondary endpoints included Duration of Response (DOR), Progression Free Survival (PFS), Overall Survival (OS), and safety.

The Overall Response Rate as assessed by an independent review committee was 46%,of whom with 3.2% of patients had a Complete Response and 42.9% achieved a Partial Response. This benefit was observed across all three subtypes of Marginal Zone Lymphomas (Overall Response Rate was 46.9%, 41.2%, and 50.0% for ENMZL/MALT, NMZL, and SMZL subtypes, respectively). The median time to response was 4.5 months and the median duration of response was not reached (range, 16.7 months – Not Reached). The most common adverse events were fatigue, diarrhea, cytopenias, nausea, peripheral edema, cough, arthralgia and dyspnea.

The authors concluded that single agent IMBRUVICA® achieved high Response Rates and durable responses in patients with Relapsed/Refractory Marginal Zone Lymphoma. IMBRUVICA® addresses an unmet need for previously treated Marginal Zone Lymphoma patients, who are in need of non-chemotherapy treatment options. Single-Agent Ibrutinib Demonstrates Efficacy and Safety in Patients with Relapsed/Refractory Marginal Zone Lymphoma: A Multicenter, Open-Label, Phase 2 Study. Noy A, de Vos S, Thieblemont C, et al. Presented at: ASH 2016 Annual Meeting and Exposition. Abstract 1213.

Chemoradiation Alone without Surgery does not Compromise Survival in Selected Patients with Rectal Cancer

SUMMARY: The American Cancer Society estimates 39,910 new cases of Rectal Cancer will be diagnosed in the United States in 2017. Rectal cancer diagnosed at an early stage such as Stage II (T3-T4, N0) or Stage III (Node positive disease without distant metastases) is potentially curable and often treated with a combination of neoadjuvant (preoperative) chemoradiation and surgery and postoperative chemotherapy. Unlike colon cancer, the risk of locoregional recurrence is high in Rectal Cancer due to its close proximity to the surrounding pelvic organs and difficulty in obtaining a clear surgical margins. Further, there is no serosal tissue surrounding the rectum. For all these reasons, preoperative Radiation Therapy (RT) with concurrent Fluoropyrimidine based chemotherapy as a radiosensitizer, followed by postoperative chemotherapy, has been the standard intervention. Radiation consists of 45 Gy delivered in 25 fractions 5 days a week with a 5.4 Gy boost. Concurrent chemotherapy in the US has included 5-FU/Leucovorin, single agent 5-FU or single agent XELODA® (Capecitabine). Complete Response is seen in approximately 25% of the patients who receive chemoradiation. However, 15% to 25% of these patients develop local recurrence. Surgery following chemoradiation may result in long term complications and may necessitate temporary or permanent colostomy in addition to sexual and urinary dysfunction.

The International Watch & Wait Database Consortium was established in 2014 by EURECCA (the European Registration of Cancer Care) and the Champalimaud Foundation in Lisbon. This Consortium which includes 35 institutions in 11 countries was established mainly to collect all available data and expand knowledge on the benefits, risks and oncological safety of organ preserving strategies, in Rectal Cancer. This database as of August 2016 included 775 patients and majority of these patients had stage T2/3 disease (92%) with clinical N0/1 nodal status (75%). Ninety percent of these patients (N=679) had a clinical Complete Response following induction therapy with chemoradiation. These patients did not undergo surgery and were followed up for a median of 2.6 years.

It was noted that 25% of all patients had local recurrence and 84% of these occurred in the first 2 years of follow up. Local recurrence was endoluminal in 96% of the patients and in the loco-regional lymph nodes in 4%. Distant metastasis occurred in 7% of the patients. The 3-year Overall Survival rate was 91% among all patients, and was 87% for patients who experienced local recurrence. These findings are comparable to survival rates seen in patients with a Complete Response, who undergo standard surgery.

It was concluded that in this largest series of patients to date with Rectal Cancer, a “watch-and-wait” strategy to treating Rectal Cancer without surgery, following Complete Response to chemoradiation, resulted in outcomes comparable to historical controls. As more information is gathered, it is important that restaging be performed in all patients with Rectal Cancer who undergo chemoradiotherapy, to prevent unnecessary surgical procedures, and give patients the option for a watch-and-wait approach. The International Watch & Wait database (IWWD) for rectal cancer: An update. van der Valk M for the International Watch and Wait Database Consortium. J Clin Oncol 35, 2017 (suppl 4S; abstract 521)

FDA Approves XERMELO® for Carcinoid Syndrome Associated Diarrhea

SUMMARY: The U.S. Food and Drug Administration on February 28, 2017 approved XERMELO® (Telotristat ethyl) tablets in combination with SomatoStatin Analog (SSA) therapy for the treatment of adults with Carcinoid syndrome diarrhea that SSA therapy alone has inadequately controlled. The hallmark of Carcinoid syndrome is excessive tumor derived serotonin secretion. Carcinoid syndrome is characterized by flushing, diarrhea, bronchial constriction, and the development of cardiac valvular fibrosis, which may lead to heart failure. Diarrhea in these patients can be debilitating with significant impact on quality of life. Serotonin is metabolized into 5-HydyroxyIndoleAcetic Acid (5-HIAA) which can be measured in the urine and is often used to follow response to treatment in patients with Carcinoid syndrome. Somatostatin analogs (SSAs) target somatostatin receptors and can regulate important cellular activity as well as help inhibit hypersecretion of hormones, including serotonin and growth hormone. This in turn can control severe diarrhea and flushing associated with metastatic Carcinoid tumors. SSAs are often used as initial treatment in this patient group, although patients may develop recurrent or progressive symptoms during the course of their disease. Tryptophan hydroxylase (TPH), the rate-limiting enzyme in serotonin synthesis, converts tryptophan to 5-hydroxytryptophan, which is then converted to serotonin.

XERMELO® is a novel, oral, small-molecule TPH inhibitor, with a high molecular weight, that reduces peripheral serotonin production by inhibiting the enzyme TPH in metastatic carcinoid tumors. XERMELO® was shown in previously published studies, to reduce bowel movement (BM) frequency and decrease urinary 5-HIAA, in patients with Carcinoid syndrome, without causing CNS adverse effects.

TELESTAR is an international, multicenter, randomized, double-blind, placebo-controlled phase III trial in which the safety and efficacy of XERMELO® was evaluated in patients with Carcinoid syndrome not adequately controlled with SSA therapy. One hundred and thirty five (N=135) patients were randomly assigned in a 1:1:1 ratio to receive oral doses of XERMELO® 250 mg, XERMELO® 500 mg, or placebo respectively, three times a day for 12 weeks. Eligible patients experienced four or more BMs per day despite treatment with a stable dose of SomatoStatin Analog (SSA). All patients continued to receive their SSA therapy for the 12 week duration. Patients were allowed to receive rescue doses of short-acting Octreotide and antidiarrheal agents. Treatment groups were well balanced and the mean age was 64 years. The primary end point was mean reduction from baseline in daily Bowel Movements (BMs), averaged over 12 weeks. Secondary end points included change in the urinary 5-HIAA from baseline at week 12, the number of daily flushing episodes, and abdominal pain severity averaged over 12 weeks. In an open-label extension study, 115 patients subsequently continued to receive XERMELO® 500 mg three times a day.

It was noted that 33% of patients randomized to the XERMELO® group experienced an average reduction of two bowel movements per day compared to only 4% of patients randomized to the placebo group. At the week 12 analysis, both XERMELO® doses significantly reduced mean urinary 5-HydroxyIndole Acetic Acid compared to placebo (P<0.001). The most common adverse events in those receiving XERMELO® ,were nausea, headache, increased levels of the liver enzyme gamma-glutamyl transferase, peripheral edema and sometimes constipation. No new safety issues were noted, when patients were followed up during the open-label extension study and patients had sustained BM responses to treatment.

It was concluded that for patients with Carcinoid syndrome not adequately controlled by SomatoStatin Analogs (SSAs), addition of XERMELO® to SSA treatment was generally safe and well tolerated and resulted in significant reductions in BM frequency and urinary 5-HydroxyIndole Acetic Acid. Telotristat Ethyl, a Tryptophan Hydroxylase Inhibitor for the Treatment of Carcinoid Syndrome. Kulke MH, Hörsch D, Caplin ME, et al. DOI: http://dx.doi.org/10.1200/JCO.2016.69.2780

Niraparib Maintenance Therapy Significantly Improves Progression Free Survival in Platinum-Sensitive Ovarian Cancer

SUMMARY: It is estimated that in the United States, approximately 22,440 women will be diagnosed with ovarian cancer in 2017 and a little over 14,000 women will die of the disease. Ovarian cancer ranks fifth in cancer deaths among women, and accounts for more deaths than any other cancer of the female reproductive system. Approximately 75% of the ovarian cancer patients are diagnosed with advanced disease and the 5 year Overall Survival rate is about 20-30%. These patients are often treated with platinum based chemotherapy following primary surgical cytoreduction.

BRCA1 and BRCA2 are tumor suppressor genes and functional BRCA proteins that repair damaged DNA and play an important role in maintaining cellular genetic integrity. They regulate cell growth and prevent abnormal cell division and development of malignancy. Mutations in BRCA1 and BRCA2 account for about 20 to 25 percent of hereditary breast cancers and about 5 to 10 percent of all breast cancers. They also account for 15 percent of ovarian cancers in addition to other cancers such as colon and prostate.

Homologous Recombination (HR) is an important pathway that allows repair of double-stranded DNA breaks and operates during the S and G2 phases of the cell cycle, relying on several proteins including BRCA1 and BRCA2. Deficiency of BRCA1 and BRCA2 results in non-functioning HR pathway (HR Deficiency), and other pathways then come in to play, which are less precise and error prone, resulting in the accumulation of additional mutations and chromosomal instability in the cell, with subsequent malignant transformation. Hereditary Epithelial Ovarian Cancer was thought to be caused almost exclusively by mutations in BRCA1 and BRCA2. It however now appears that about 50% of the high grade serous ovarian cancers have aberrations in HR repair pathway. BRCA mutations can either be inherited (germline) and present in all individual cells or can be acquired and occur exclusively in the tumor cells (somatic). Somatic mutations account for a significant portion of overall BRCA1 and BRCA2 aberrations, and loss of BRCA function due to frequent somatic aberrations in ovarian cancers likely deregulates HR pathway and increases sensitivity to platinum drugs. Majority of the women with germline BRCA mutations (gBRCA) are positive for HR deficiency.

The PARP (Poly ADP Ribose Polymerase) family of enzymes which include PARP1 and PARP2, repair damaged DNA. PARP inhibitors kill tumors defective in the BRCA1 or BRCA2 genes through the concept of synthetic lethality. Epithelial Ovarian Cancers with Homologous Recombination Deficiency (HRD) have demonstrated sensitivity to PARP inhibitors. The two currently FDA approved PARP inhibitors include LYNPARZA® (Olaparib) for the treatment of ovarian cancer with gBRCA mutations after three lines of therapy and RUBRACA® (Rucaparib) for the treatment of ovarian cancer with gBRCA mutations and /or somatic mutations after two lines of therapy.

Niraparib is a highly selective PARP 1/2 inhibitor, that detects DNA damage and promotes its repair. Previously published studies demonstrated the antitumor activity of Niraparib in patients with ovarian cancer, at a maximum dose of 300 mg per day, with a low frequency of high grade adverse events. Based on this preliminary data, the authors conducted a randomized, placebo-controlled, phase III trial (ENGOT-OV16/NOVA) to evaluate the efficacy and safety of Niraparib versus placebo, as maintenance treatment in patients with platinum-sensitive, recurrent ovarian cancer.

This study enrolled two independent cohort of patients based on the presence or absence of a germline BRCA mutation (gBRCA cohort and non-gBRCA cohort), as determined on BRACAnalysis® testing (Myriad Genetics). All enrolled patients had tumors sensitive to platinum-based therapy and had received at least 2 lines of therapy. Enrolled patients (N=553) were randomly assigned in a 2:1 ratio to receive Niraparib 300 mg or placebo once daily. The gBRCA cohort included 203 patients (138 assigned to Niraparib and 65 to placebo) and the non-gBRCA cohort included 350 patients (234 assigned to Niraparib and 116 to placebo). The Primary end point was Progression Free Survival (PFS) and Secondary end points included chemotherapy-free interval, time to first subsequent therapy, Overall Survival and safety.

It was noted that patients in the Niraparib group had a significantly longer Progression Free Survival compared to those in the placebo group. In the gBRCA cohort, the PFS with Niraparib compared to placebo was 21.0 vs. 5.5 months (HR=0.27), in the non-gBRCA cohort for patients who had tumors with Homologous Recombination Deficiency (HRD), the PFS was 12.9 months vs. 3.8 months (HR=0.38) and for the overall non-gBRCA cohort, the PFS was 9.3 months vs. 3.9 months (HR=0.45). The P value was significant for all three comparisons (P<0.001). The most common grade 3 or 4 toxicities in the Niraparib group were thrombocytopenia (34%), anemia (25%), and neutropenia (20%), and this was managed with dose modifications.

The authors concluded that among patients with platinum-sensitive, recurrent ovarian cancer, Niraparib significantly prolonged Progression Free Survival compared to placebo and this benefit was achieved regardless of the presence or absence of gBRCA mutations or HRD status, with acceptable toxicities. Niraparib Maintenance Therapy in Platinum-Sensitive, Recurrent Ovarian Cancer. Mirza MR, Monk BJ, Herrstedt J, et al. N Engl J Med 375:2154-2164, 2016

IBM Artificial Intelligence Platform Highly Concordant with Physician Recommendations

SUMMARY: Watson for Oncology, is an Artificial Intelligence (AI) computer developed by IBM in collaboration with Memorial Sloan Kettering Cancer Center. This revolutionary tool has the advanced ability to analyze the meaning and context of structured and unstructured data in the patients chart and is able to assimilate key patient information and then deliver evidence based treatment recommendations, through analytical approaches. The authors conducted this study to assess concordance between the Artificial Intelligence platform, Watson for Oncology (WFO) and their own multidisciplinary tumor board, which comprised of a group of 12 to 15 oncologists, who met weekly to review cases from their hospital system. The goal of the study was to understand how Watson for Oncology would impact oncologists day-to-day practice, and how Watson’s recommendations compared to the decisions of their team of experts.

The researchers studied 638 patients with breast cancer treated at Manipal Comprehensive Cancer Center in Bengaluru, India. Patient data was entered into the Watson for Oncology (WFO) computer system and the degree of concordance between WFO’s recommendations and those of the tumor board were analyzed, in addition to the time it took for each group to come up with their recommendations. In this study, WFO analyzed more than 100 patient attributes for breast cancer and provided treatment options ranked as follows – Recommended Standard Treatment (REC), For Consideration (FC) and Not Recommended (NREC). These recommendations provided by WFO were evidence based and the computer system allowed the treating physicians to learn more about the recommendations and the rationale behind those recommendations.

It was noted that 90% of WFO’s Recommendations for Standard Treatment (REC) and For Consideration (FC) were concordant with the recommendations of the tumor board. WFO recommendations were concordant nearly 80% of the time in non-metastatic breast cancer, but only 45% of the time in metastatic disease. In patients with triple-negative breast cancer, WFO agreed with the physicians 68% of the time, but in HER-2 negative cases, WFO’s recommendations matched the physician’s recommendations only 35% of the time. The authors attributed the difference in concordance to fewer treatment options for triple-negative breast cancer, compared to HER-2 negative breast cancer. Further, including HER-2 patients made more treatment options available and this would increase the demands on human thinking capacity. Additionally, more complicated cases lead to more divergent opinions on the recommended treatment.

This study also compared the amount of time it took to provide recommendations, after the data was captured and analyzed. It took an average of 20 minutes when done manually, but after gaining more familiarity with the cases, the time decreased to about 12 minutes. Watson for Oncology by comparison, took a median time of 40 seconds to capture and analyze data and give a treatment recommendation.

It was concluded that while Artificial Intelligence is a step towards personalized medicine, it should not be viewed as a replacement for a physician, but rather as a complement. In the end, the best treatment option for the patient should be determined together by the treating physician and the patient. Double blinded validation study to assess performance of IBM artificial intelligence platform Watson for oncology in comparison with Manipal multidisciplinary tumor board—first study of 638 breast cancer cases. Somashekhar SP, Kumar R, Rauthan A, et al. Presented at: San Antonio Breast Cancer Symposium, Friday, Dec. 9, 2016; San Antonio, TX. Abstract S6-07

Dual Inhibition Improves Outcomes for Patients with BRAF-Mutated Colorectal Tumors

SUMMARY: ColoRectal Cancer (CRC) is the third most common cancer diagnosed in both men and women in the United States. The American Cancer Society estimates that approximately 135,430 new cases of ColoRectal Cancer will be diagnosed in the United States in 2017 and over 50,260 patients are expected to die of the disease. The DNA MisMatchRepair (MMR) system is responsible for molecular surveillance and works as an editing tool that identifies errors within the microsatellite regions of DNA and removes them. Defective MMR system leads to MSI (Micro Satellite Instability) and hypermutation, triggering an enhanced antitumor immune response. MSI (Micro Satellite Instability) is therefore a hallmark of defective/deficient DNA MisMatchRepair (MMR) system and occurs in 15% of all colorectal cancers. Defective MisMatchRepair can be a sporadic or heritable event. Approximately 65% of the MSI tumors are sporadic and MSI-High tumors tend to have better outcomes. Patients with stage IV colorectal cancer are now routinely analyzed for extended RAS and BRAF mutations. KRAS mutations are predictive of resistance to Epidermal Growth Factor Receptor (EGFR) targeted therapy. Approximately 5-10% of all metastatic CRC tumors present with BRAF V600 mutations and BRAF V600 is recognized as a marker of poor prognosis in this patient group. These patients tend to have aggressive disease with a higher rate of peritoneal metastasis and do not respond well to standard treatment intervention. Approximately 25% of the BRAF-mutated population in the metastatic setting has MSI-High tumors, but MSI-High status does not confer protection to this patient group.

The Mitogen-Activated Protein Kinase pathway (MAPK pathway) is an important signaling pathway which enables the cell to respond to external stimuli. This pathway plays a dual role, regulating cytokine production and participating in cytokine dependent signaling cascade. The MAPK pathway of interest is the RAS-RAF-MEK-ERK pathway. The RAF family of kinases includes ARAF, BRAF and CRAF signaling molecules. BRAF is a very important intermediary of the RAS-RAF-MEK-ERK pathway. The BRAF V600 mutations results in constitutive activation of the MAP kinase pathway. Inhibiting BRAF can transiently reduce MAP kinase signaling. However, this can result in feedback upregulation of EGFR signaling pathway, which can then reactivate the MAP kinase pathway. This aberrant signaling can be blocked by dual inhibition of both BRAF and EGFR.

ZELBORAF® (Vemurafenib), is a selective oral inhibitor of mutated BRAF whereas ERBITUX® (Cetuximab) is a monoclonal antibody targeting Epidermal Growth Factor Receptor (EGFR). Preclinical studies have shown that adding CAMPTOSAR® (Irinotecan) to ZELBORAF® and ERBITUX®, in patients with refractory BRAF V600E metastatic CRC, led to a durable responses and this combination was safe and tolerable. However, both single agent ZELBORAF® and ERBITUX® were shown to have limited activity in this patient group.

Based on this scientific rationale, a phase II trial was conducted (SWOG 1406), in which 106 metastatic ColoRectal Cancer patients, with mutations in BRAF V600 and extended RAS wild-type, were enrolled. Patients were randomized to receive CAMPTOSAR® 180 mg/m2 IV every 14 days and ERBITUX® 500 mg/m2 IV every 14 days, with or without ZELBORAF® 960 mg orally twice daily. The median age was 62 years and about 50% of patients had received 1 prior regimen for metastatic or locally advanced unresectable metastatic CRC, and 39% had received prior treatment with CAMPTOSAR® . Prior therapy with anti-EGFR agent or RAF or MEK inhibitors was not allowed. Crossover from the control arm to the experimental group was allowed, after documented disease progression. The primary endpoint was Progression Free Survival.

The median Progression Free Survival was 4.4 months with the triplet, versus 2.0 months with CAMPTOSAR® plus ERBITUX® (HR=0.42; P =0.0002). The response rate was 16% versus 4%, and the Disease Control Rate was 67% versus 22% (P =0.001), with a higher Duration of Response with the addition of ZELBORAF® to CAMPTOSAR® and ERBITUX® (Triplet). Approximately 50% of the patients in the control group crossed over to the experimental group at the time of disease progression. Overall Survival data and efficacy at cross-over, data, remain immature. Patients in the experimental group (Triplet group) experienced more grade 3/4 toxicities such as neutropenia, anemia and nausea, and this increase was attributed to increased duration of exposure to therapy.

The authors concluded that the addition of ZELBORAF® to the combination of CAMPTOSAR® and ERBITUX® resulted in a 58% reduction in the risk of disease progression and a higher Disease Control Rate, suggesting that simultaneous EGFR and BRAF inhibition (Dual Inhibition) is effective in BRAF V600 mutated ColoRectal Cancer. Subgroup analysis will examine the role of CAMPTOSAR® pre-treatment and the outcomes of patients based on tumor MicroSatellite Instability. Randomized trial of irinotecan and cetuximab with or without vemurafenib in BRAF-mutant metastatic colorectal cancer (SWOG 1406). Kopetz S, McDonough SL, Morris VK, et al. J Clin Oncol 35, 2017 (suppl 4S; abstract 520)

GAZYVA® Superior to RITUXAN® in Follicular Lymphoma

SUMMARY: The American Cancer Society estimates that in 2017, about 72,240 people will be diagnosed with Non Hodgkin Lymphoma (NHL) in the United States and about 20,140 individuals will die of this disease. Indolent Non Hodgkin Lymphomas are mature B cell lymphoproliferative disorders and include Follicular Lymphoma, Nodal Marginal Zone Lymphoma (NMZL), Extranodal Marginal Zone Lymphoma (ENMZL) of Mucosa-Associated Lymphoid Tissue (MALT), Splenic Marginal Zone Lymphoma (SMZL), LymphoPlasmacytic Lymphoma (LPL) and Small Lymphocytic Lymphoma (SLL). Follicular Lymphoma is the most indolent form and second most common form of all NHLs and they are a heterogeneous group of lymphoproliferative malignancies. Approximately 20% of all NHLs are Follicular Lymphomas. Advanced stage indolent NHL is not curable and as such, prolonging Progression Free Survival (PFS) and Overall Survival (OS), while maintaining Quality of Life, have been the goals of treatment intervention. Asymptomatic patients with indolent NHL are generally considered candidates for “watch and wait” approach. Patients with advanced stage symptomatic Follicular Lymphoma are often treated with induction chemoimmunotherapy followed by maintenance RITUXAN® (Rituximab). This can result in a median Progression Free Survival (PFS) of 6-8 yrs and a median Overall Survival of 12-15 yrs. However, approximately 30% of the patients will relapse in 3 years.

GAZYVA® (Obinutuzumab) is glycoengineered, fully humanized, third generation, type II anti-CD20 antibody (IgG1 monoclonal antibody) that selectivity binds to the extracellular domain of the CD20 antigen on malignant human B cells. By virtue of binding affinity of the glycoengineered Fc portion of GAZYVA® to Fcγ receptor III on innate immune effector cells (natural killer cells, macrophages and neutrophils), Antibody-Dependent Cell-mediated Cytotoxicity (ADCC) and Antibody-Dependent Cellular phagocytosis are significantly enhanced, but induces very little Complement-Dependent Cytotoxicity. This is in contrast to RITUXAN® which is a first generation type I, chimeric, anti-CD20 targeted monoclonal antibody that kills lymphoma cells primarily by Complement-Dependent Cytotoxicity and also ADCC.

GAZYVA® along with Bendamustine in the phase III GADOLIN study, prolonged PFS, compared with Bendamustine alone, in patients with relapsed/refractory indolent Non Hodgkin lymphoma. Based on this promising data, the GALLIUM phase III trial was conducted in treatment naïve patients with Follicular Lymphoma. This study included 1,202 patients with newly diagnosed Follicular Lymphoma, who had Grade I-IIIa tumors and had an ECOG PS of 2 or less. Patients were randomized to receive either GAZYVA® plus chemotherapy, followed by GAZYVA® maintenance (N=601), or RITUXAN® plus chemotherapy, followed by RITUXAN® maintenance (N=601). The chemotherapy regimens used were CHOP, CVP or Bendamustine, based on the discretion of the treating physician. Patients received either RITUXAN® 375mg/m2 IV on day 1 of each cycle or GAZYVA® 1000 mg IV on days 1, 8, and 15 of cycle 1 and day 1 of subsequent cycles, for either eight 21-day cycles (CHOP and CVP) or six 28-day cycles (Bendamustine). Patients who achieved a complete response (CR) or partial response (PR) at the end of induction therapy, received maintenance therapy with RITUXAN® or GAZYVA® every 2 months for 2 years or until disease progression. The median age was 59 years and 57.1% of patients received Bendamustine, 33.1% received CHOP, and 9.8% received CVP. The primary endpoint was PFS and secondary endpoints included Response Rate, Overall Survival (OS), Disease Free Survival and safety. Upon recommendations from the Independent Monitoring Committee, the study was unblinded after a preplanned interim efficacy analysis.

After a median follow-up of 34.5 months, patients in the GAZYVA® group had a 34% reduction in the risk of progression or death compared with those in the RITUXAN® group (HR=0.66; P=0.001). There was however no difference between the two treatment groups in the 3-year Overall Survival (OS) rate (P=0.21). Response rates were similar in both GAZYVA® and RITUXAN® treatment groups. Patients treated with GAZYVA® had more serious adverse events, 46.1% versus 39.9% in the RITUXAN® group, but the discontinuation rate was similar in both treatment groups.

The authors concluded that for treatment naïve Follicular Lymphoma patients, combining GAZYVA® with chemotherapy resulted in a clinically meaningful improvement in PFS compared with RITUXAN® plus chemotherapy and should therefore be the new standard of care for this patient population. Obinutuzumab-Based Induction and Maintenance Prolongs Progression-Free Survival (PFS) in Patients with Previously Untreated Follicular Lymphoma: Primary Results of the Randomized Phase 3 GALLIUM Study. Marcus RE, Davies AJ, Ando K, et al. Presented at the 58th American Society of Hematology (ASH) Annual Meeting. December 3-6, 2016; San Diego, CA. Abstract 6.