Phase II Trial of Ribociclib Plus Letrozole in Women With Recurrent Low-Grade Serous Carcinoma of the Ovary, Fallopian Tube, or Peritoneum: A GOG Partners Trial (GOG 3026)
PURPOSE Low-grade serous carcinoma (LGSOC) of the ovary, fallopian tube, or peritoneum is a hormonally driven, relatively chemoresistant malignancy with limited treatment options in the recurrent setting. Given frequent estrogen receptor (ER) expression and dysregulation of the cyclin-dependent kinases 4 and 6 (CDK4/6)–p16–Rb pathway, features shared with hormone receptor–positive breast cancer, dual endocrine, and CDK4/6 inhibition is a biologically rational strategy. This phase II trial evaluated ribociclib plus letrozole in recurrent LGSOC. METHODS This open-label, single-arm, multicenter phase II study enrolled women with measurable, recurrent LGSOC. Patients received ribociclib (600 mg orally, once daily, days 1-21 of a 28-day cycle) and letrozole (2.5 mg orally, once daily). The primary end point was investigator-assessed objective response rate (ORR) per RECIST 1.1. Secondary end points included clinical benefit rate (CBR), progression-free survival (PFS), overall survival (OS), and safety. RESULTS Of 74 patients screened, 51 were enrolled and 49 treated. The confirmed ORR was 30.6% (90% CI, 19.9 to 43.2), including one complete and 14 partial responses. Among responders, the median duration of response was 21.2 months. The CBR was 84% (90% CI, 72.5 to 91.6). The median PFS was 14.5 months (90% CI, 10.1 to 28.8), and the median OS was 44.5 months (90% CI, 31.8 to not reached). The most common grade ≥3 adverse event (AE) was neutropenia (47%), managed with dose modifications. Three grade 5 events (6%) occurred but were unrelated to treatment. Treatment discontinuation because of AEs occurred in 4%. No dose-limiting toxicities were observed. CONCLUSION Ribociclib plus letrozole met the primary end point, achieving meaningful response rates and durable disease control in recurrent LGSOC. The safety profile was consistent with prior CDK4/6 inhibitor studies. This combination represents a therapeutic option in this rare and genomically distinct subtype.
Ovarian cancer patients’ and their family members’ perspectives on novel vaccine and virotherapy trials
Background/aims: Some of the most promising avenues of cancer clinical investigation center on immunotherapeutic approaches. These approaches have provided notable gains in cancer therapeutics with recent Food and Drug Administration approvals of agents of this class in several types of cancers, although gains for ovarian cancer lag behind. This study examined perceptions of therapeutic trials including immunotherapy and virotherapy among ovarian cancer patients and their family members. Methods: A total of 72 semi-structured qualitative interviews were conducted with 33 patients and 39 family members at two National Cancer Institute–designated comprehensive cancer centers. Eligible patients were diagnosed with epithelial ovarian, primary peritoneal, or fallopian tube carcinoma and had experience with clinical trial conversations; family members were nominated by patients and interviewed separately. Applied thematic analysis was used to understand and interpret the data. Results: More participants were aware of vaccine trials than virus trials, although more than half had heard of at least one of them. Initial reactions to vaccine trials were generally favorable. For many, childhood experience with vaccines lent a familiar frame of reference. Virus trials elicited more negative initial reactions, including the use of adjectives such as “scary” and “dreadful.” Viruses seemed contagious or difficult to control. Increased receptivity to these trials occurred in the context of limited therapeutic options and cancer recurrence. Most participants, including those not immediately drawn to these types of trials, indicated openness to learning more. Conclusion: Although vaccine and viral trials are both immunologically based therapeutic approaches, patients who are offered these trials may perceive their potential benefit and safety quite differently. There is a need to consider terminology, solicit and address “gut reactions,” and provide information that enables patients and their family members to better understand the science behind these trials.