LIÈGE, BELGIUM & GRENOBLE, FRANCE -- PDC*line Pharma, a clinical-stage biotech company developing a new class of potent and scalable active immunotherapies for cancers, today announces the interim results from the last cohort of patients in its phase I/II clinical trial (PDC-LUNG-101, NCT03970746) with PDC*lung01.

PDC*lung01 is the company’s off-the shelf therapeutic cancer vaccine candidate for Non-Small Cell Lung Cancer (NSCLC). The preliminary data on the last cohort of patients was presented today through both an oral presentation and a poster at the American Association for Cancer Research (AACR) Annual Meeting 2024. This data revealed that the high dose PDC*lung01 combined with pembrolizumab shows an immunological activity in a majority of patients and a promising antitumor response in stage IV NSCLC with a mild safety profile.

The phase I/II trial (PDC-LUNG-101) aimed to assess the safety, tolerability, immunogenicity and preliminary clinical activity of PDC*lung01 in NSCLC patients, alone or in combination with anti-PD-1 treatment. PDC*lung01 was administered weekly through both subcutaneous and intravenous routes, in six consecutive doses. The trial was conducted across 17 clinical sites in France, Belgium, Germany, the Netherlands and Poland. PDC*lung01 was administered to a total of 67 evaluable HLA-A*02:01 positive NSCLC patients, at two dose levels and settings:

· As a single agent in the adjuvant setting (cohorts A1: Low Dose, A2: High Dose)
· Combined with standard of care anti-PD-1 monotherapy in first-line stage IV (metastatic) NSCLC patients with a PD-L1 tumor proportion score of ≥50% and no targetable driver mutation (cohorts B1: Low Dose, B2: High Dose)

Clinical activity parameters such as Objective Response Rate (ORR) and Progression-Free Survival (PFS) were assessed only in cohorts B1 and B2. The B2 cohort included 45 patients. PDC*Line is reporting preliminary efficacy results for 19 evaluable patients in the B2 cohort that reached the 9-month PFS mark.

Key highlights from the oral presentation
Title: Preliminary clinical results of a therapeutic cancer vaccine PDC*lung01 in combination with anti-PD-1 in patients with Stage IV NSCLC

· PDC*lung01 treatment at high dose with pembrolizumab exhibited a mild safety profile
At database cut-off, 38 patients started treatment. Out of the 21 patients in the B2 cohort who started treatment and reached the 9-month follow-up, 19 received at least 5 doses of PDC*lung01 and had 1 post-baseline radiological evaluation, qualifying them as evaluable per protocol. Overall, the high dose of PDC*lung01 showed an acceptable safety profile. Most of the treatment-related AEs were consistent with AEs associated with SC/IV injections of other vaccines, or with AEs already observed in clinical trials of anti-cancer vaccines. The evaluation of the SAEs reported did not identify any safety concerns.

· PDC*lung01 demonstrated biological activity in triggering an antitumor immune response in the majority of patients
A peptide-specific and effector memory CD8+ T-cell response was induced against the lung antigens of PDC*lung01 in 68.4% of patients. Immune responses with remarkable expanded anti-tumor CD8+ T-cells were observed in both Partial Response and Stable Disease patients. More immune response results will be available in the final analysis of the 45 patients in cohort B2.

· PDC*lung01, in combination with pembrolizumab, is associated with a promising objective response rate and progression free survival in first line setting stage IV NSCLC patients
With the 19 evaluable patients, the median follow-up at the database lock was 12.5 months (95% CI: 9.9, 14.2). The Best Objective Response (BOR) included 12 Partial Response (63.2%) and 7 Stable Disease (36.8%) with ORR of 63.2% (80% CI 45.9 - 78.2) and a Disease Control Rate (DCR) of 94.7% (80% CI: 81, 99.4). The 9-month PFS according to the Kaplan-Meier estimate was 52.1% (80% CI 36.5 - 65.56). The median PFS was 10.9 months (95% CI 5.6 - Not Reached). The median duration of response was 9.49 months (95% CI: 4.4, -).

The safety, immunological and clinical activity results from the B2 cohort are consistent with the data from the first three cohorts of patients (A1, A2 and B1) that were presented at ESMO 2022 in September 2022 in Paris (France) and ESMO-IO in December 2022 in Geneva (Switzerland).

The final analysis of the clinical trial including the 45 patients from the B2 cohort will be conducted in Q3, 2024.

“PDC*lung01 in combination with anti-PD-1 showed very promising signals suggesting that this combination could offer a clinically meaningful tumor response in stage IV NSCLC patients, along with an interesting mild safety profile,” said Prof Johan Vansteenkiste, emeritus professor in respiratory oncology at KU Leuven in Belgium and chair of the Data and Safety Monitoring Board (DSMB).

“These interim results have real potential; this is a very encouraging step for the company. We are looking forward to sharing the complete set of data when the B2 cohort is complete,” said Dr. Beatrice De Vos, chief medical officer at PDC*line Pharma.

“We are excited to share these very favourable results for our innovative cancer vaccine. The objective response rate of 63.2% and the median progression free survival of 10.9 months along with a mild safety profile are in line with our targets. We’re also encouraged by the evidence of immune response observed in patients, which supports the mechanism of action of PDC*lung01 in relation to clinical activity,” said Eric Halioua, CEO of PDC*line Pharma.