Wright, Alexi A.

5515 Background: Clear cell ovarian carcinoma (CCOC) is a chemoresistant subtype of ovarian cancer. Immune checkpoint inhibitors have been reported to have clinical activity in CCOC. Additionally, CCOC harbors molecular alterations suggesting a role for anti-angiogenic agents. We therefore conducted a single-arm two-stage phase 2 trial to investigate the clinical activity of the combination of the PD-1 inhibitor pembrolizumab with the anti-angiogenic tyrosine kinase inhibitor lenvatinib in patients (pts) with CCOC. Methods: Pts with CCOC and measurable disease received pembrolizumab 200 mg IV every 3 weeks and lenvatinib 20 mg daily. Pts could have received an unlimited number of prior therapies; prior bevacizumab and immune checkpoint inhibitors were allowed, but prior lenvatinib was exclusionary. Malignant bowel involvement was not allowed. Co-primary endpoints were objective response rate (H 0 5%; H a 25%) and rate of PFS at 6 months (mo) per RECIST v1.1 (H 0 10%; H a 30%), restricting the probabilities of type I and type II errors to 10% and 10%, respectively. Two pts with objective responses or 3 pts progression-free and alive at 6 mos were needed to proceed from stage 1 (n=18) to stage 2 (n=13); 5 pts with objective responses or 6 pts progression-free and alive at 6 mos were needed to declare the combination worthy of further study. Results: Data cut-off occurred 22-Oct-2024. Of 30 enrolled pts, 83.3% were white; the mean age among all pts was 54.1 years. 30% of pts (9/30) experienced a confirmed response (2 CR, 7 PR); an additional 3 pts (10%) experienced unconfirmed PRs and 4 pts (13.3%) had SD ≥6 mo. As of data cut-off, 3 pts (10%) had not yet reached their first radiographic assessments, and 17 pts were still receiving study therapy. With a median of 9.72 mo of follow up, 16 pts were alive and progression-free at 6 months. The estimated 6-month PFS was 75.96% (95% CI 53.82-88.51%). Median PFS was 10.9 mo. The estimated 12-month PFS was 48.86% (95% CI 23.67-70.04%). The most common any-grade TRAEs were hypertension (71%), hypothyroidism (66%), and fatigue (60%). There were no unanticipated TRAEs. Conclusions: The combination of pembrolizumab/lenvatinib demonstrates encouraging evidence of clinical activity in CCOC, with 9 pts experiencing a confirmed response and 16 pts alive and progression-free at 6 months. As both co-primary endpoints of the study were met, enrollment closed with 30 pts. Updated data for all pts will be reported. There were no new safety signals. Clinical trial information: NCT05296512 .

Purpose To provide guidance to clinicians regarding the use of neoadjuvant chemotherapy and interval cytoreduction among women with stage IIIC or IV epithelial ovarian cancer. Methods The Society of Gynecologic Oncology and the American Society of Clinical Oncology convened an Expert Panel and conducted a systematic review of the literature. Results Four phase III clinical trials form the primary evidence base for the recommendations. The published studies suggest that for selected women with stage IIIC or IV epithelial ovarian cancer, neoadjuvant chemotherapy and interval cytoreduction are noninferior to primary cytoreduction and adjuvant chemotherapy with respect to overall and progression-free survival and are associated with less perioperative morbidity and mortality. Recommendations All women with suspected stage IIIC or IV invasive epithelial ovarian cancer should be evaluated by a gynecologic oncologist prior to initiation of therapy. The primary clinical evaluation should include a CT of the abdomen and pelvis, and chest imaging (CT preferred). Women with a high perioperative risk profile or a low likelihood of achieving cytoreduction to < 1 cm of residual disease (ideally to no visible disease) should receive neoadjuvant chemotherapy. Women who are fit for primary cytoreductive surgery, and with potentially resectable disease, may receive either neoadjuvant chemotherapy or primary cytoreductive surgery. However, primary cytoreductive surgery is preferred if there is a high likelihood of achieving cytoreduction to < 1 cm (ideally to no visible disease) with acceptable morbidity. Before neoadjuvant chemotherapy is delivered, all patients should have confirmation of an invasive ovarian, fallopian tube, or peritoneal cancer. Additional information is available at www.asco.org/NACT-ovarian-guideline and www.asco.org/guidelineswiki .