Island completes dosing in phase 2b arm of mosquito-borne dengue trial

Island Pharmaceuticals has completed subject dosing for the phase 2b therapeutic arm of its phase 2a/b PROTECT clinical trial of ISLA-101 in dengue fever.

Island is aiming to slap down mosquito-borne dengue fever. Pic via Getty Images.

• Island completes phase 2b therapeutic arm of PROTECT clinical trial of ISLA-101 for treatment of dengue fever

• Phase 2b follows promising results in the phase 2a arm and favourable SRC review observing anti-viral activity in ISLA-101-treated subjects

• High-level results of phase 2b trial anticipated in the next six to eight weeks

Special Report: Australian antiviral drug development company Island Pharmaceuticals has completed subject dosing for the phase 2b therapeutic arm of its phase 2a/b PROTECT clinical trial of ISLA-101 to combat mosquito-borne dengue fever.

Island Pharmaceuticals Ltd (ASX:ILA)said the 10 subjects in the phase 2b cohort were successfully administered ISLA-101 on schedule and with no delays.

The phase 2 PROTECT study is divided into two cohorts including a phase 2a prophylactic (preventative) and a phase 2b therapeutic (treatment) cohort.

The phase 2b arm of the trial is designed to assess if ISLA-101 can reduce virus levels and symptoms in a subject already infected with the dengue challenge virus, which is an attenuated or weakened strain of dengue.

Subject enrolment for the phase 2b arm started in January 2025 following a positive assessment by the company’s Safety Review Committee (SRC) on data from Island’s phase 2a cohort.

Review of the data by the SRC determined that key benchmarks for safety and anti-dengue activity had been met, providing Island with a strong platform to proceed to phase 2b trials for the therapeutic application of the treatment.

The SRC’s recommendations were lodged with the US Food and Drug Administration (FDA) for the recommended 30-day review period prior to the start of the phase 2b cohort.

Between the two studies, Island said it aimed to understand if ISLA-101 can be an effective prophylactic and/or therapeutic against a dengue infection.

Island said the primary endpoint of phase 2b is viremia (virus load in the bloodstream) reduction in subjects.

Other endpoints include confirming the safety of ISLA-101 and a reduction in the symptoms associated with dengue infection.

Island noted that high-level results from the phase 2b studies were anticipated in the next six to eight weeks.

Treatment ‘could aid millions’

Dengue fever is the most prevalent mosquito-borne viral disease and, according to the World Health Organization, its incidence has grown dramatically around the world in recent decades, with no specific treatment.

Island executive chairman Phil Lynch said the opportunity for the company was both significant in scale and increasingly positive.

“The most recent 2a clinical results show the potential for a preventative approach to dengue management that could aid millions of travellers who visit exposed countries, with malaria treatment a useful analogue to quantify this opportunity,” he said.

“We look forward to further positive results from the 2b trial, and thereafter the opportunity to progress ISLA-101 as a potential therapeutic treatment also, for what remains a significant unmet consumer healthcare need.”

This article was developed in collaboration with Island Pharmaceuticals, a Stockhead advertiser at the time of publishing.

This article does not constitute financial product advice. You should consider obtaining independent advice before making any financial decisions.

Originally published as Island completes dosing in phase 2b arm of mosquito-borne dengue trial