Kura Oncology announces results from AIM-HN study of tipifarnib

Kura Oncology announced results from its registration-directed AIM-HN study of tipifarnib in patients with HRAS mutant head and neck squamous cell carcinoma, or HNSCC, whose disease is recurrent or metastatic and has progressed after prior therapy. These clinical results are being featured during a late-breaking oral session at the 2023 European Society for Medical Oncology, or ESMO, Congress in Madrid, Spain, in a presentation titled, “A phase 2 study evaluating tipifarnib in mHRAS, recurrent or metastatic, or R/M, head and neck squamous cell carcinoma.” The abstract is now available on the ESMO website and the presentation will be available in the Posters and Presentations section on Kura‘s website at the start of the poster session on Saturday, October 21. As of the data cutoff on June 15, 59 patients with R/M HRAS mutant HNSCC were enrolled, of whom 50 had high HRAS mutant variant allele frequency and 38 were evaluable for efficacy. The following table compares response assessed between the investigators and the independent review facility, in the modified intent to treat high VAF population. Both assessments by investigators and IRF observed one patient achieving a CR on treatment. Patients had a median of two prior lines of therapy in the recurrent/metastatic setting and robust activity was seen in second line treatment and beyond with greater activity observed in the second line versus the third line and subsequent treatments. The ORR in second line treatment was 29% in the IRF assessment. The ORR for three FDA-approved therapies for the treatment of HNSCC in the second line range from 13-16%. Patients in the AIM-HN trial received tipifarnib at a dose of 600 mg orally twice daily on days 1-7 and 15-21 of 28-day cycles. Tipifarnib was generally well-tolerated with a manageable safety profile. The most common grade 3 or 4 treatment-related adverse events, or TRAEs, seen in at least 10% of patients were cytopenias and TRAEs led to discontinuation of treatment in 7% of patients.