French-based biotechnology company Transgene announced in June 2023 that new data confirm that its novel investigational therapeutic cancer vaccine can induce immune responses against HPV16. The results are presented in a poster at the American Society of Clinical Oncology meeting in Chicago.
HPV16 is known as a “high-risk” human papillomavirus. Alongside HPV18 it causes most HPV-related cancers. The CDC suggests that type 16 is the cause of “approximately 50% of cervical cancers worldwide”. According to Transgene, treatment options “remain limited”.
The vaccine is an investigational viral vector based therapeutic cancer vaccine, based on non-propagative, highly attenuated Vaccinia vector (MVA). This has been engineered to express the HPV antigens E6 and E7. It also features an adjuvant: interleukin 2 (IL-2).
Transgene states that the vaccine is designed to “have a two-pronged approach”. The first element is to “alert the immune system specifically to cells presenting the HPV E6 and E7 antigens”, which are found in HPV16-related tumours. The second is to “further stimulate the infection-clearing activity of the immune system through interleukin 2”.
TG4001 in trial
TG4001 is under evaluation in a randomised controlled Phase II clinical study. The study compares TG4001 in combination with avelumab to avelumab in isolation. The patients enrolled in the study have HPV16-positive anogenital tumours.
46 patients have been included in both arms of the trial. A statement from Transgene suggests that 58% of patients who received the combination of TG4001 and avelumab demonstrated increased immune responses against HPV antigens, compared to 9% in the avelumab arm.
“These data clearly demonstrate that Transgene’s TG4001 could induce a specific immune response against the antigens vectorised within this vaccine.”
Results are expected in 2024, with the last patient to be randomised in the first half of that year.
Dr Alessandro Riva, Chairperson and CEO of Transgene commented that the team is “excited” by the data.
“These data further confirm that our therapeutic vaccine TG4001 can induce clinically meaningful immune responses, that are associated with antitumour response.”
The company looks forward to the final analysis of the study and the “potential next steps”.