Investigator
University Of Groningen
Vvax001, a Therapeutic Vaccine, for Patients with HPV16-Positive High-grade Cervical Intraepithelial Neoplasia: A Phase II Trial
Abstract Purpose: Human papillomavirus (HPV) infection is the major cause of (pre)malignant cervical lesions. We previously demonstrated that Vvax001, a replication-incompetent Semliki Forest virus vaccine encoding HPV type 16 (HPV16) E6 and E7, induced potent anti-E6 and -E7 cytotoxic T-cell responses. In this study, we investigated the clinical efficacy of Vvax001 in patients with HPV16-positive cervical intraepithelial neoplasia (CIN) grade 3 (CIN3). Patients and Methods: Patients with newly diagnosed HPV16-positive CIN3 were eligible for participation. Patients received three immunizations of Vvax001 (5 × 107 infectious particles) at a 3-week interval. Up to 19 weeks after the last immunization, patients were monitored for regression of CIN3 by colposcopy. A colposcopy-guided biopsy was taken at the last visit, and a standard-of-care loop excision was performed only in case of remaining CIN grade 2/CIN3. Histopathologic response rates, HPV16 clearance, treatment-related adverse events, and vaccine-induced immune responses were assessed. Results: A total of 18 patients were enrolled and fully immunized. Colposcopic examination revealed a reduction in CIN3 lesion sizes in 17/18 (94%) patients already evident from 3 weeks onward after the last immunization. A histopathologic complete response (regression to CIN grade 1 or no dysplasia) was observed in 9/18 patients (50%) and HPV16 clearance in 10/16 patients (63%). Vvax001 did not induce clearance of other HPV types. To date, no recurrences have been observed, with a median and longest disease-free survival of 20 and 30 months, respectively. No serious adverse events were observed. Conclusions: Treatment with Vvax001 is safe and feasible and shows preliminary clinical effectiveness in patients with HPV16-associated CIN3 lesions.
Neoadjuvant immune checkpoint blockade in women with mismatch repair deficient endometrial cancer: a phase I study
Neoadjuvant immune checkpoint blockade (ICB) has shown unprecedented activity in mismatch repair deficient (MMRd) colorectal cancers, but its effectiveness in MMRd endometrial cancer (EC) remains unknown. In this investigator-driven, phase I, feasibility study (NCT04262089), 10 women with MMRd EC of any grade, planned for primary surgery, received two cycles of neoadjuvant pembrolizumab (200 mg IV) every three weeks. A pathologic response (primary objective) was observed in 5/10 patients, with 2 patients showing a major pathologic response. No patient achieved a complete pathologic response. A partial radiologic response (secondary objective) was observed in 3/10 patients, 5/10 patients had stable disease and 2/10 patients were non-evaluable on magnetic resonance imaging. All patients completed treatment without severe toxicity (exploratory objective). At median duration of follow-up of 22.5 months, two non-responders experienced disease recurrence. In-depth analysis of the loco-regional and systemic immune response (predefined exploratory objective) showed that monoclonal T cell expansion significantly correlated with treatment response. Tumour-draining lymph nodes displayed clonal overlap with intra-tumoural T cell expansion. All pre-specified endpoints, efficacy in terms of pathologic response as primary endpoint, radiologic response as secondary outcome and safety and tolerability as exploratory endpoint, were reached. Neoadjuvant ICB with pembrolizumab proved safe and induced pathologic, radiologic, and immunologic responses in MMRd EC, warranting further exploration of extended neoadjuvant treatment.