In March 2023, Vaccitech announced top-line interim data from a Phase Ib/II clinical trial of its VTP-200 vaccine in women with low-grade cervical human papillomavirus (HPV) lesions. The vaccine is intended to treat HPV infections, catching them before the virus causes high-grade lesions. The data was described as a “promising step” with more to come in early 2024.  

HPV 

Vaccitech states that an estimated 291 million women across the world are “carriers” of HPV DNA. Persistent genital HPV infection is “responsible for almost all cases of cervical pre-cancerous lesions”, which can lead to cervical carcinoma.  

“Over 95% of cervical cancers are caused by HPV infection.”  

WHO indicates that the two most common “high-risk” genotypes cause around 70% of all cervical cancerrs.  

“HPV was estimated to cause almost half a million cases and 250,000 deaths from cervical cancer in 2002.” 

Although there are two prophylactic vaccines against HPV, it continues to cause problems globally.  

HPV001 and VTP-200 

HPV001 is a fully-enrolled, randomised, placebo-controlled multi-centre trial to evaluate the safety, efficacy, and immunogenicity of VTP-200. The study consists of an “open label, non-randomised, dose escalation lead-in phase of 9 participants”. This is followed by a “blinded, randomised main phase of approximately 96 participants with high-risk HPV”.  

VTP-200 is a “investigational heterologous prime boost immunotherapy” comprising an initial dose using the ChAdOx vector and a second dose using MVA. Both encode the same HPV antigens to elicit an immune response to HPV.  

Promising data 

Data from the first 58 women enrolled who reached their 6-month timepoint in the study were reviewed with the trial expected to continue as planned to the 12-month endpoint. Immunogenicity results showed “high responses”. This was defined by Vaccitech as an “average greater than 1,000 spot-forming units per million peripheral blood mononuclear cells in an ELISPOT assay”.  

VTP-200 was “generally well-tolerated”. Bill Enright, CEO of Vaccitech, described the data as a “promising step in the right direction”, stating that he looks forward to final data next year”. 

“Currently people with persistent HPV infection have no treatment options until they develop high grade lesions.” 

Enright referred to repeat cervical screening without a treatment option as a “frustrating and anxiety-provoking” approach. 

We look forward to hearing more from Vaccitech at the World Vaccine Congress in Washington. If you would like to join us, get your tickets here.