PDS Biotechnology (PDSB) Status Update summary

FDA Meeting Outcomes and Clinical Strategy

• FDA alignment achieved for the Phase 3 VERSATILE-003 trial of Versamune HPV plus pembrolizumab in HPV16-positive head and neck cancer, with initiation set for Q4 2024 and Fast Track designation granted.

• The FDA supported advancing both double and triple combination strategies, requesting additional safety analysis for the triple combination and a separate dose optimization study for PDS01ADC.

• Preparatory work for the trial is underway, with a CRO contracted and strong investigator and site interest.

• The company aims to establish Versamune HPV plus pembrolizumab as the first targeted immunotherapy for HPV16-positive HNSCC.

• No outstanding FDA issues remain for the VERSATILE-003 trial start; the switch from bintrafusp alfa to pembrolizumab simplifies regulatory pathways.

Clinical Data and Trial Design

• VERSATILE-002 phase II trial met its primary endpoint, showing a 34% ORR (CPS≥1), 21% of patients with >90% tumor shrinkage, a 77.4% disease control rate, and median overall survival of 30 months, exceeding historical benchmarks.

• The doublet demonstrated a favorable safety profile, with 9.2% grade 3 and 1.1% grade 4 treatment-related toxicity, and no grade 5 events; most common non-injection site adverse events were fatigue, headache, and diarrhea.

• The phase III VERSATILE-003 trial will randomize 400-450 patients 2:1 to Versamune HPV plus pembrolizumab versus pembrolizumab alone, with overall survival as the primary endpoint and interim/futility analyses planned.

• Biomarker data confirm induction of tumor-infiltrating CD8+ T cells and clearance of circulating tumor DNA, correlating with clinical responses.

• Addition of PDS01ADC to Versamune HPV and checkpoint inhibitors in early studies shows potential for deeper anti-tumor responses and prolonged survival, with a 75% ORR and median OS of 42 months in first-line HPV16+ cancers.

Market Opportunity and Business Update

• The market for late-stage recurrent/metastatic HPV16-positive head and neck cancer is estimated at $1.5–$3 billion, with a US annual incidence of 18,000 cases and rising.

• Current therapies improve response and progression-free survival but have not significantly extended overall survival, highlighting unmet needs.

• The company is leveraging Fast Track designation for ongoing FDA engagement and aims for rapid patient access.

• The pipeline includes additional studies in cervical, oropharyngeal, and MUC1+ cancers, with multiple investigator-initiated and NCI-supported trials ongoing.

• Updates on the triple combination and further data presentations are expected later in the year, with key milestones for 2024–2025 including regulatory confirmation and multiple Phase 2 data readouts.