FDA Approvals in Breast Cancer and Prostate Cancer, Priority Review in Breast Cancer, and More

Today-

FDA approvals in breast cancer and prostate cancer, a priority review designation in breast cancer, a breakthrough therapy designation in renal cell carcinoma, and new drug applications in acute myeloid leukemia and multiple myeloma.

Welcome to OncLive News Network! I'm Gina Columbus.

The FDA has approved upfront ribociclib for use in combination with an aromatase inhibitor for the treatment of pre or perimenopausal or postmenopausal women with hormone receptor-positive/HER2-negative advanced or metastatic breast cancer.

Ribociclib was also approved for use in combination with fulvestrant for the treatment of postmenopausal women with HR-positive/HER2-negative advanced or metastatic disease in the frontline setting or after disease progression on endocrine therapy.

The decision for the ribociclib/AI regimen was based on the phase III MONALEESA-7 trial, which showed that combining ribociclib with an AI resulted in a 14-month improvement in median progression-free survival versus an AI alone.

The approval for ribociclib plus fulvestrant was based on data from the phase III MONALEESA-3 trial, in which the median PFS was 20.5 months in patients randomized to the ribociclib combination versus 12.8 months in those randomized to fulvestrant plus placebo.

This marks the first approval that the FDA has granted as a part of two new pilot programs announced earlier this year, which are Real-Time Oncology Review and Assessment Aid.

Under Real-Time Oncology Review, the FDA can review pivotal clinical trial data as soon as it becomes available, prior to the formal submission of an application. Assessment Aid is a new template for submitting an application that is structured to facilitate a streamlined process for the agency to review the application.

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In prostate cancer, the FDA has approved enzalutamide for the treatment of patients with nonmetastatic castration-resistant prostate cancer.

The approval is based on findings from the double-blind, phase III PROSPER trial, in which the combination of enzalutamide and androgen deprivation therapy reduced the risk of metastases or death by 71% compared with ADT alone for patients with nonmetastatic CRPC. In the study, the median metastasis-free survival was 36.6 months with enzalutamide plus ADT versus 14.7 months with ADT alone.

Additionally, there was a 93% reduction in the risk of prostate-specific antigen progression in the enzalutamide arm versus ADT alone. The median time to PSA progression in the enzalutamide group was 37.2 months versus 3.9 months for ADT alone.

At the time of the analysis, overall survival data were not yet mature; however, there was a trend toward improvement in OS with the addition of enzalutamide.

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In triple-negative breast cancer, the FDA granted a priority review designation to a biologics license application for the antibody-drug conjugate sacituzumab govitecan for the treatment of patients with metastatic triple-negative breast cancer following at least 2 prior therapies for metastatic disease.

Phase II findings with sacituzumab govitecan showed an objective response rate of 34% in patients with heavily pretreated metastatic TNBC. In the 110-patient, single-arm trial, the ORR was accompanied by stable disease for more than 6 months in 11% of patients, for an overall disease control rate of 45%. The median progression-free survival with sacituzumab govitecan was 5.5 months and the median overall survival was 12.7 months.

Under the Prescription Drug User Fee Act, the FDA is scheduled to make its decision on the BLA by January 18, 2019.

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The FDA has granted the combination of atezolizumab and bevacizumab a breakthrough therapy designation for use in combination with bevacizumab as a first-line treatment for patients with advanced or metastatic hepatocellular carcinoma.

The decision is based on a phase Ib study in which independent reviewers determined that at a median follow-up of 10.3 months, atezolizumab and bevacizumab induced an overall response rate of 65% among 23 evaluable patients.

The 65% ORR comprised a complete response rate of 4% and a partial response rate of 61%. Additionally, 7 patients had stable disease and 1 patient had progressive disease. A disease control rate of more than 6 months was reported for 16 patients.

The ongoing phase III IMbrave150 study is comparing atezolizumab/bevacizumab with sorafenib in the frontline setting for patients with locally advanced or metastatic HCC.

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In acute myeloid leukemia, a supplemental new drug application has been submitted to the FDA for venetoclax in combination with a hypomethylating agent or low-dose cytarabine for the first-line treatment of patients who are ineligible for intensive chemotherapy.

The application is based on 2 phase Ib/II trials in this setting, which are the M14-358 study and the M14-387 study. In M14-358, combining venetoclax with azacitidine or decitabine led to a complete remission or CR with incomplete blood count recovery rate of 73%. The median overall survival at more than 1 year of follow-up was 17.5 months.

The open-label phase Ib/II dose escalation and expansion M14-387 study examined venetoclax in combination with LDAC. The CR/CRi rate with the combination in this study was 62%. The median OS at more than 1 year of follow-up was 11.4 months.

The FDA breakthrough designation expedites the development and review of treatments that have demonstrated early potential to improve outcomes over standard therapy for a serious condition.

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A rolling submission of an FDA new drug application has been submitted for selinexor for the treatment of patients with penta-refractory multiple myeloma.

The application is based on data from part 2 of the phase IIb STORM trial, in which selinexor induced an overall response rate of 25.4% in patients with penta-refractory disease. The responses included 2 complete responses and 29 partial responses or very good partial responses. The median duration of response was 4.4 months.

Prior data from part I of the study showed that selinexor achieved an ORR of 20.5% in 78 patients with quad- or penta-refractory myeloma.

Karyopharm, the manufacturer of selinexor, reported in a press release that they plan to complete the NDA by the end of 2018. The FDA previously granted selinexor both orphan drug and fast track status in this setting.

Karyopharm intends to present full data from the phase IIb STORM trial at an upcoming oncology conference.

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This week, we sat down with Dr Adi Diab, of The University of Texas MD Anderson Cancer Center, to discuss immunotherapy progress in oncology and role of interleukin-2.

That’s all for today.

Thank you for watching OncLive News Network! I'm Gina Columbus.