Dr Price on the Potential Role for HPV-Targeted Immunotherapy Vaccines in HPV+ HNSCC

Katharine A. Price, MD, associate professor, oncology, consultant, Division of Medical Oncology, Department of Oncology, Mayo Clinic, discusses the potential role for injectable HPV-targeted immunotherapy vaccines for patients with HPV16-positive head and neck squamous cell carcinoma (HNSCC).

Several HPV-targeted vaccines are currently being investigated within the HNSCC treatment space, with the most promising data emerging in the first-line recurrent/metastatic setting in combination with checkpoint inhibitors. Although there are some studies looking at these vaccines in treatment-refractory patients, the response rate in that population tends to be lower, Price states. Ongoing trials are also exploring the use of therapeutic vaccines without immunotherapy, she notes. Based on the trajectory of current trials, it is likely that the first indication for these vaccines will be in patients with recurrent/metastatic disease and a combined positive score (CPS) of 1 or greater, Price speculates.

According to data presented at the 2024 ASCO Annual Meeting, patients with a CPS of 20 or higher may derive more benefit from these vaccines, similar to what is observed with immunotherapy, Price reports. Some trials are now restricting enrollment to patients with a CPS of 20 or higher, although the planned phase 3 VERSATILE-003 trial will enroll patients with a CPS of 1 or greater, she notes. However, for patients with PD-L1–negative disease, a treatment gap may still exist with the emergence of these therapeutic vaccines, Price says.

Another interesting area of investigation with therapeutic vaccines is in patients with biochemical or molecular recurrences, Price continues. With the increasing use of circulating tumor DNA (ctDNA) assays in routine practice, more patients are being identified who have rising ctDNA levels after curative-intent treatment but no evidence of disease, she elaborates. In these cases, it is conceivable that therapeutic vaccines could be used to prevent or delay significant recurrence, with ctDNA levels serving as a marker for treatment response, Price states.

As research progresses, therapeutic vaccines are likely to become integrated into various treatment paradigms, including the curative-intent setting. For now, the focus remains on studying these vaccines in the first-line recurrent/metastatic disease space, Price concludes.