Phase 1 Gamma-PN Trial Shows Promising Safety and Immune Response

GPN Vaccines, a clinical-stage biotechnology firm, has reported favorable safety and immunogenicity outcomes from its Phase 1 clinical trial of Gamma-PN, a novel whole cell-pneumococcal vaccine. This vaccine is intended for adults aged 50 to 69 years and aims to prevent severe forms of pneumonia, bacteraemia, and meningitis caused by the Streptococcus pneumoniae bacteria.

The trial was a double-blind, randomized study that included placebo and active controls. It involved 120 participants who were administered two doses each of either 50, 250, or 1000 micrograms of Gamma-PN, with 30 participants per dosage group. Additionally, some participants received a single dose of an existing pneumococcal vaccine, such as Pneumovax-23® or Prevenar 13®, while others received a placebo.

The primary safety objective of the study was successfully met, indicating that Gamma-PN has a safety profile that is promising for further development. The vaccine did not cause any serious adverse events, and its systemic tolerability was deemed excellent. Reactions at the injection site were generally mild to moderate, consisting of redness and swelling that typically lasted for one to two days. The frequency and severity of these reactions were related to the dosage administered. The tolerability after the second dose was found to be similar to that after the first dose.

An immunological evaluation was conducted to measure serum IgG responses to the Gamma-PN vaccination. An ELISA test, developed and operated by a third-party laboratory accredited by GLP (Good Laboratory Practice), showed that the vaccine induced an increase in serum IgG levels in a dose-dependent manner after both doses. The activation of neutrophils in the vaccinated participants was consistent with the vaccine's ability to stimulate innate immune responses.

Further immunological tests are being carried out by GPN Vaccines on serum and peripheral blood mononuclear cells (PBMCs). These tests include the assessment of opsonophagocytic antibodies against various Streptococcus pneumoniae serotypes, both those covered by current vaccines and those not covered. The results of these additional tests will be reported once they are fully completed.

Professor Paul Rolan, the Chief Medical Officer of GPN Vaccines, expressed gratitude to the clinical trial participants and highlighted that the study showed Gamma-PN to be safe and well-tolerated, with the appropriate dosages selected for further clinical development.

Dr. Tim Hirst, the Chief Executive Officer and co-founder of the company, expressed delight at the positive clinical trial results for their broad-spectrum pneumococcal vaccine, which is designed to protect against all serotypes of Streptococcus pneumoniae. He stated that these results provide crucial insights for dose selection in upcoming Phase 2 clinical trials.

The clinical trial was supported by a generous grant of $1 million from the South Australian Government's Research and Innovation Fund (RIF). GPN Vaccines is developing a vaccine to combat Streptococcus pneumoniae, which is responsible for causing significant mortality rates worldwide, particularly among children. The company's product, Gamma-PN, is intended to protect against all strains of the bacteria, irrespective of serotype.