The study was conducted in India in a population that had not previously been treated with immunotherapy, but the results are likely applicable even when patients have been exposed to these agents, according to Rushabh Kothari, MD, DM, who presented the study (Abstract LBA6004), at the annual meeting of the American Society of Clinical Oncology (ASCO).
Although immunotherapy is considered the first-line therapy for the disease, it is often unavailable in low- and middle-income countries: In India, about 3% of head and neck cancer patients receive it, Dr. Kothari said during his presentation.
The study offered improved outcomes and greater tolerability in this population, according to Dr. Kothari. “Metronome chemotherapy led to an improvement [in both OS and PFS] of around 2 months compared to physician’s choice of treatment in this difficult-to-treat population, and metronomic chemotherapy had multiple advantages [over other chemotherapies]. It is an oral treatment, there is an ease of administration, and it is very cost effective. It also lowers adverse events as we saw in the data,” said Dr. Kothari, a medical oncologist at Narayana Multispeciality Hospital in India, in an interview.
The improvement is meaningful given the dire circumstances these patients find themselves in, according to Dr. Kothari: “When you see a second-line relapsed metastatic head and neck cancer, their overall survival is dismal: It is less than 7 months with most of the available agents,” he said in the interview.
Metronomic chemotherapy is continuous, low-dose chemotherapy that includes an anti-angiogenic effect, according to Dr. Kothari. In the current study, the researchers employed a triple metronomic chemotherapy (TMC) that included methotrexate (9 mg/m2 weekly), erlotinib (150 mg daily), and celecoxib (200 mg twice daily), which was compared to any of eight single-agent physician choice agents, all of which were consistent with National Comprehensive Care Network (NCCN) guidelines (NCCN-PC group).
Study methods and results
The study included 55 patients in the TMC arm and 59 in the NCCN-PC arm. Currently, 13 patients in the TMC arm and 6 in the NCCN-PC are still being treated.
More than 94.5% of the TMC arm and 91.5% of the NCCN-PC arm had previously received platinum-based therapy, and 49.1% and 47.5%, respectively, had received taxane.
The median OS was 181 days in the TMC group, versus 123 days in the NCCN-PC group (hazard ratio, 0.5076; 95% confidence interval, 0.325-0.792). The median PFS was 120 days and 70 days, respectively (HR, 0.4941; 95% CI, 0.312-0.738).
Adverse events were less frequent in TMC, including anemia (grade 3-5, 3.7% versus 14.8%; P = .038), neutropenia (0% versus 13.0%; P =.006), thrombocytopenia (0% versus 9.3%; P = .028), serum glutamic-oxaloacetic transaminase/serum glutamic-pyruvic transaminase (SGOT/SGPT) rise (0% versus 9.3%; P = .028), creatinine rise (0% versus 9.3%; P = .028), and diarrhea (1.9% versus 13.0%; P = .006).
“When you give lower doses continuously, the compliance is very good. When tolerance is good and compliance is good, that is the ideal regimen, which patients want,” said Dr. Kothari in the interview.
Dr. Kothari pointed out that the study included primarily patients with oral cavity cancers, including 89.1% of the TMC group and 83.1% of the NCCN-PC group. Oropharyngeal cancers are more common in high-income countries, but his own clinical experience suggests that the combination also performs well in that group, he said.
During a discussion part of the session, Ezra Cohen, MD, said that when pembrolizumab was moved from second-line to first-line therapy, it left an unmet need in second-line recurrent or metastatic disease.
He welcomed the new results.
“[The study shows] a much better toxicity profile with the triple metronomic therapy. In other words, we can deliver these reagents at the doses prescribed, with a toxicity profile I would say that is not only manageable, but that is in fact favorable. In addition to that, in a limited size phase III study, we see an improvement in the primary endpoint here of overall survival. So in a patient population that may not necessarily have access to anti-PD1 antibodies, we can offer a lower cost triple regimen that does appear to improve survival over standard regimens,” said Dr. Cohen, who is chief medical officer of Tempus.
Dr. Kothari has received honoraria from Alkem Laboratories, AstraZeneca, Bard Peripheral Vascular, Bristol Myers Squibb Foundation, Celon Pharma, Cipla, Emcure, Fresenius Kabi, Glenmark, Merck, Novartis, Pfizer, Roche, and Zydus Pharmaceuticals. He has consulted for or advised MSD. He has received research funding through his institution from Axis Clinicals, Lambda Therapeutic Research, Reliance Life Sciences, and Zydus Pharmaceuticals.
Dr. Cohen is an employee of Tempus and has held leadership positions at Akamis Bio, Kinnate Biopharma, Kura Oncology, and Pangaea Biotech. He has stock or other ownership interests in Kinnate Biopharma and Primmune Therapeutics. He has consulted for or advised Adagene, Astellas Pharma, Cidara, Eisai, Genmab, Gilboa Therapeutics, ITeos Therapeutics, Lilly, Merck, MSD, Nectin Tx, Novartis, Nykode Therapeutics, Pangea, PCI Biotech, Replimune, Roche, SOTERIA Precision Medicine, and Viracta Therapeutics.
