Non-small cell lung cancer vaccine harnesses peptides to increase immune response.
Vaxon, a biopharmaceutical company, recently announced positive results from a phase 2b clinical trial of Vx-001 in patients with non-small cell lung cancer (NSCLC). Vx-001 is a candidate cancer vaccine that is based on optimized cryptic tumor peptides, according to a press release.
Included in the study were 190 patients with metastatic and distant recurrent NSCLC who responded to first-line platinum chemotherapy. All patients included were HLA-A2-positive and had tumors that expressed the TERT antigen, which was targeted by the vaccine.
Patients were randomized to receive Vx-001 (89 patients) or placebo (101 patients). The primary endpoint was overall survival (OS), and secondary endpoints were time-to-treatment failure and OS at 12 months.
The investigators found that the candidate vaccine was highly effective among patients who never smoked or who had smoked for less than 20 years, classified as light smokers, with non-immunogenic tumors.
Among these patients, OS was 20.2 months compared with 7.9 months for the placebo group, according to the study. Time-to-treatment failure was higher for the subgroup of patients treated with Vx-001 at 5.6 months compared with 3.3 months for placebo patients.
The most notable improvement was in 12-month survival. Patients in the subgroup treated with the vaccine had an 80% increase in survival, while placebo patients only saw an 8% increase, according to the study.
Due to the prevalence of immune checkpoint inhibitors as later therapies, the findings provide data as a surrogate combination study finding higher survival for patients previously treated with checkpoint inhibitors and then with Vx-001 compared with placebo, according to the release.
These findings suggest that the candidate vaccine may change cold tumors into hot tumors to harness the immune system in response for certain subtypes, according to the study.
“We are very excited about these great results and the potential of our vaccine,” said Kostas Kosmatopoulos, MD, PhD, CEO and founder of Vaxon. “As immune checkpoint inhibitors are not hugely effective in patients with non-immunogenic NSCLC, Vaxon’s Vx-001 could bring a significant clinical benefit for these patients. There is potential to be used either as a stand-alone therapy or together with immune checkpoint inhibitors. Preliminary results of this study suggest that Vx-001 can render sensitive tumors that are initially resistant to immune checkpoint inhibitors. It could also mean a potential for wider application in cancers where current immune checkpoint inhibitors are ineffective.”
Vx-001 is the first and only vaccine to use optimized cryptic peptides, which are tumor peptides. Although these normally go undetected by the immune system, they are modified to increase the anti-cancer response.
The optimized cryptic peptides avoid immune tolerance and do not need to be personalized, as they are essentially universal neo-antigens, according to the release. Since these peptides can treat a variety of patients, there is an opportunity for widespread use.
Vaxon is currently finalizing a confirmatory study to analyze the results observed in the subgroup, who were HLA-A2 positive, negative for EGFR and ALK mutations, in the never or light smoker population, with no immunity in stage 4 NSCLC after 4 cycles of platinum-based chemotherapy. This target population represents more than 22,000 patients annually, according to the release.
“I’m very happy with these results because they show a clear clinical benefit in patients who are not sensitive to immune checkpoint inhibitors and have few therapeutic options. Rendering sensitive tumor that are resistant to immune checkpoint inhibitors is a major goal in cancer treatment and it may concern not only NSCLC but many other tumors that because of their low mutation load are not immunogenic,” said principal investigator Vassilis Georgoulias, MD, PhD.