regardless of programmed death–ligand 1 (PD-L1) expression, according to preliminary findings from a phase 2 study.
Apatinib, an inhibitor of vascular endothelial growth factor receptor-2, and camrelizumab, an anti-PD-1 monoclonal antibody, produced an objective response rate of 60% in evaluable patients.
Chunyan Lan, MD, of Sun Yat-sen University Cancer Center in Guangzhou, China, and colleagues reported these resultsthat had been slated for presentation at the Society of Gynecologic Oncology’s Annual Meeting on Women’s Cancer. The meeting was canceled because of the COVID-19 pandemic. The following data differ somewhat from the abstract.
Dr. Lan and colleagues reported results in 45 patients who had progressed after at least one line of systemic chemotherapy for metastatic, recurrent, or persistent cervical cancer, and had measurable disease. Patients had a median age of 51 years and an Eastern Cooperative Oncology Group performance status of 0-1. They were enrolled at four centers in China between Jan. 21 and Aug. 1, 2019.
Treatment consisted of oral apatinib at a dose of 250 mg once daily and intravenous camrelizumab at a dose of 200 mg every 2 weeks until disease progression, unacceptable toxicity, or consent withdrawal.
As of Jan. 22, 2020, 25 of 42 efficacy-evaluable patients had achieved a response. Two patients had a complete response, 23 had a partial response, and 12 had stable disease.
“We saw responses in patients regardless of PD-L1 expression,” Dr. Lan said. “In our study, 34% were PD-L1 negative, and the response rate is 65% in PD-L1-positive and 50% in PD-L1-negative [patients].”
The median duration of response was not reached, she added.
The median follow-up was 9.2 months, with the last patient enrolled having 6 months of follow-up. At the data cutoff, 19 patients had disease progression, and 8 had died of their disease.
The median overall survival also was not reached, Dr. Lan said, but overall survival at 9 months was 80%. The median progression-free survival was 7.6 months, and the 6-month progression-free survival rate was 58%.
Grade 3 or greater treatment-related adverse events occurred in 68.9% of patients; adverse events occurring in at least 5% of patients included hypertension (22.2%), fatigue (15.6%), anemia (13.3%), and thrombocytopenia (6.7%).
“Nineteen patients were still on treatment at the data cutoff date, and 26 patients discontinued the study,” Dr. Lan said. “The most common reason to discontinue was disease progression, and three patients discontinued the study due to adverse events.”
“These preliminary results are very encouraging,” Dr. Lan said. “As we know, pembrolizumab is approved as the second-line therapy in recurrent cervical cancer [in] PD-L1-positive patients, and the objective response rate with pembrolizumab monotherapy for recurrent cervical cancer is only 17%, as reported in.”
Furthermore, apatinib monotherapy has been studied with only modest results.
“But in our study, this combination is really effective in recurrent cervical cancer, and we see a very durable response,” she said, again emphasizing that those responses occurred regardless of PD-L1 expression. “So this is important. ... We think our findings expand the opportunity of patients with recurrent cervical cancer to receive immune therapy.”
Study participants will be followed for 2 years, Dr. Lan noted.
She reported having no disclosures. The study is sponsored by Sun Yat-sen University.
SOURCE: Lan C et al. SGO 2020, .