Tisotumab Vedotin Yields Promising Preliminary Activity in SCCHN

Treatment with tisotumab vedotin (Tivdak) resulted in promising safety and antitumor activity in a population of patients with squamous cell carcinoma of the head and neck (SCCHN) who progressed following treatment with a platinum-based chemotherapy regimen and a checkpoint inhibitor, according to preliminary findings from the phase 2 innovaTV 207 study (NCT03485209).

Results from the study, which were presented at the 2022 Multidisciplinary Head and Neck Cancers Symposium, showed a confirmed partial response rate of 16.1% and an overall disease control rate of 58.1%, along with a tolerable safety profile. Among the 31 patients receiving tisotumab vedotin, 16 had stable disease, 8 had progressive disease, and 2 were not evaluable. The median progression-free survival (PFS) for patients was 4.2 months (95% CI, 2.7-4.8 months), while the median overall survival (OS) was 9.4 months (95% CI, 8.1-11.8 months).

“You can see [from the study results] that 79% of the evaluable patients had a reduction from baseline in their target lesion,” said May Cho, MD, who presented the results of the SCCHN analysis of the innovaTV 207 study during a live presentation.

InnovaTV 207 is an ongoing open-label multicenter trial enrolling across the United States and Europe looking at the use of 2 mg/kg of tisotumab vedotin given intravenously every 3 weeks. Patients with SCCHN on the trial had up to 3 systemic treatments previously and a median duration of treatment of 12 weeks (range, 3-36 weeks).

“Based on looking at the toxicity profile there is a bit of stasis, and then ocular and neuropathy, AEs, so I think that [the patient’s tissue] has some expressions [for patients with head and neck cancer],” explained Cho when discussing the tissue expression factors of patients on the trial.

At least 1 or more treatment-emergent adverse events (TEAEs) were observed in all 31 patients in the SCCHN cohort of the innovaTV 207 study, but according to Cho these were all manageable. Twenty-eight patients had TEAE related to the use of tisotumab vedotin. There was one fatal TEAE, but it was not related to tisotumab vedotin. The most common grade 3 AEs related to tisotumab vedotin were anemia in 10% of patients and asthenia in 6%. Additionally, the most common grade 1/2 AEs related to tisotumab vedotin were nausea, myalgia, and epistaxis in 29% of patients each.

The median age of patients on the treatment arm were 65 years old. Fourteen patients had primary tumor surgery and 24 had primary tumor radiation. Prior systemic regimens included checkpoint inhibitors in 27 patients, cetuximab in 18 patients, and all 31 patients were at least given platinum-based therapy.

These data, according to researchers, are enough to warrant further study with tisotumab vedotin in this patient population. Cho said further studies will look at treatment with tisotumab vedotin.

“Part D [of the innovaTV 207] study is looking at the treatment-naive patients in the first line setting with pembrolizumab and platinum doublet therapy with tisotumab vedotin every 3 weeks,” Cho said when talking about the future of tisotumab vedotin in the SCCHN setting. “Part C of the study looks at patients in the second line and beyond on 1.7 mg/kg of tisotumab vedotin on day 1 and 15, every 28 days.”

Reference

Hong DS, Birnbaum A, Steuer C, et al. Efficacy and safety of tisotumab vedotin in patients with head and neck squamous cell carcinoma: results from a phase II cohort. Presented at: 2022 Multidisciplinary Head and Neck Cancers Symposium; February 24-26, 2022; Phoenix, Arizona. Accessed February 25, 2022. https://bit.ly/3tl6Pjc