Sequential chemoradiotherapy (CRT) and immunotherapy is safe, well tolerated, and efficacious among patients with locally advanced cervical cancer being treated with curative intent, a multicenter phase 1 trial suggests.
Less than 10% of patients treated with this sequence experienced a grade 3 toxicity. Meanwhile, more than 80% were alive and free of disease progression at 1 year.
“Despite standard CRT, most women with lymph node–positive cervical cancer experience disease recurrence,” note the investigators, led by Jyoti S. Mayadev, MD, associate professor in the department of radiation medicine and applied sciences, University of California, San Diego, in La Jolla. “Our study is potentially transformative in the standard treatment schema of locally advanced cervical cancer, with the prospect for immuno-oncology to add durable survival in patients with node-positive disease, a current unmet oncologic need.”
The investigators enrolled in the trial 32 women from Gynecology Oncology Cooperative Group member institutions who had stage IB2 to IVA cervical cancer with positive pelvic and/or para-aortic lymph nodes. Treatment consisted of six weekly doses of cisplatin, 40 mg/m2, concurrent with extended-field, 3-dimensional conformal radiotherapy, followed by the immune checkpoint inhibitor ipilimumab (Yervoy) every 21 days for four cycles.
Results reported in JAMA Oncology showed that all 32 patients completed CRT and 21 patients went on to receive ipilimumab. Among the latter, 86% completed all four planned cycles and the rest completed two cycles.
In the group receiving sequential CRT and ipilimumab, 9.5% experienced grade 3 toxicity (lipase increase in one case and dermatitis in another case). Both toxicities were self-limited.
With a 14.8-month median follow-up, the patients treated with CRT-ipilimumab had a 12-month overall survival rate of 90%, and a 12-month progression-free survival rate of 81% (median durations were not reached). Neither human papillomavirus genotype nor HLA subtype was associated with these outcomes.
Translational analyses showed that patients experienced an increase in peripheral blood T cells expressing programmed cell death 1 (PD-1) after CRT that was then sustained with ipilimumab therapy. “[T]he use of an immune checkpoint inhibitor could stimulate the antitumor activity of tumor-specific cytotoxic T cells and augment radiation-induced neoantigen load,” the investigators proposed.
“To our knowledge, this phase 1 study is the first to show tolerability with a signal of efficacy of an immune check-point inhibitor ... as a part of the definitive treatment of locally advanced cervical cancer,” they concluded. “Our findings show promise for the use of immunotherapy in the definitive setting of locally advanced, node-positive cervical cancer; patients with this cancer historically have a poor prognosis with standard therapy alone.”
Dr. Mayadev disclosed receiving a grant from the National Cancer Institute during the conduct of the study, personal fees from AstraZeneca, grants from NRG Oncology, and personal fees and nonfinancial support from the Gynecology Oncology Group Foundation outside the submitted work; receiving compensation for serving on the advisory board of Varian Medical Systems in 2018; and being a speaker for Samsung Medical Systems in 2017. The study was supported by the National Cancer Institute and by institutional funds.
SOURCE: Mayadev JS et al. JAMA Oncol. 2019 Nov 27. doi: 10.1001/jamaoncol.2019.3857.