Shanghai Ark Biopharmaceutical Co Ltd ('ArkBio') on Thursday reported positive top-line Phase II study results for its novel anti-fibrotic drug AK3280 in treating idiopathic pulmonary fibrosis (IPF).

The study was led by Professor Huaping Dai of the Department of Pulmonary and Critical Care Medicine at China-Japan Friendship Hospital, Beijing, across 31 clinical sites in China.

AK3280 is a new generation broadly active antifibrotic drug optimised for pharmacological and pharmacokinetic properties based on current IPF drugs, showing enhanced anti-fibrotic activity and improved pharmacokinetic properties, and absent of gastrointestinal tolerability issues and other toxicities associated with current therapeutics.

Previous Phase I studies have demonstrated its favourable safety, tolerability, and human pharmacokinetic profile.

In the Phase II trial, participants were randomised to receive AK3280 (100/200/300/400 mg BID) or placebo for 24 weeks. Clinical efficacy endpoints included forced vital capacity of lung (FVC and %pFVC), diffusing capacity of lung for carbon monoxide (DLco), the 6-minute walk test (6MWT) and patient reported St. George's Respiratory Questionnaire (SGRQ) scores. The high dose groups demonstrated FVC improvement from baseline, especially the 400 mg group which had the absolute FVC increased by 209.4 mL and a 6.4% adjusted %pFVC improvement from baseline, which is statistically significant compared to placebo (p=0.002 and 0.004, respectively). Other lung and respiratory functions also improved.

ArkBio noted that the drug exhibited a good safety and tolerability profile without the gastrointestinal intolerability issues associated with current IPF therapeutics.

AK3280 is a potential next-generation broad-spectrum anti-fibrotic molecule optimised from the marketed drug that modulates multiple pathways and biomarkers closely associated with the fibrotic process. It reduces fibroblast cellular proliferation and inhibits the synthesis and accumulation of extracellular matrix.

The Phase II clinical study has been completed, with a pivotal Phase III study expected to be forthcoming.