Alnylam Pharmaceuticals has completed enrolment for its ILLUMINATE-A Phase III study of lumasiran to treat adults and children with primary hyperoxaluria type 1 (PH1).

The six-month randomised, double-blind, placebo-controlled, global, multi-centre study will evaluate the efficacy and safety of lumasiran in around 30 patients with a documented diagnosis of PH1.

Patients were enrolled across 16 sites in eight countries.

Topline results from the study are expected late this year. If the results are positive, filings will be submitted for global regulatory approvals starting early next year.

During the study, patients are randomised in 2:1 format to receive three monthly doses of lumasiran or placebo at 3mg/kg followed by quarterly maintenance doses.

The primary endpoint of the trial is the percentage change in 24-hour urinary oxalate excretion from months three to six relative to baseline in patients treated with the investigational RNAi therapeutic compared to placebo.

Additional measures of urinary oxalate, plasma oxalate, estimated glomerular filtration rate (eGFR), safety and tolerability will be evaluated for key secondary and exploratory endpoints.

Alnylam Lumasiran programme vice-president and general manager Pritesh Gandhi said: “We are pleased to have reached two important milestones for our PH1 programme, timely completion of enrollment in ILLUMINATE-A, our Phase III pivotal study in adults and children, and successful completion of our Phase I/II study with positive final results.

“We look forward to reporting topline results from the ILLUMINATE-A study expected in late 2019 and believe that lumasiran has the potential to provide a clinically meaningful treatment option for patients living with PH1.”

Alnylam also reported complete positive results from its Phase I/II clinical study and reiterated positive results from its ongoing Phase II open-label extension (OLE) study of lumasiran.