GRIN Therapeutics has dosed the first participant in the Phase IB Honeycomb clinical trial of radiprodil to treat GRIN-related disorders.

The open-label trial has been designed for assessing the pharmacokinetics, tolerability, safety, and effects on seizures, sleep, and behavioural symptoms, as well as motor functions of several individually titrated radiprodil doses in the indicated children.

Up to 24 participants aged between six months and 12 years with confirmed gain-of-function (GoF) variants causing GRIN-related disorders, including variants on GRIN2A, GRIN2B, GRIN2D, and GRIN1, will be included in the trial.

The company stated that the trial will comprise a cohort of individuals who have experienced drug-resistant seizure frequency at least once weekly, and a cohort of patients with behavioural and other symptoms who have experienced fewer or no seizures.

A screening period, a titration period, and a maintenance period on the highest tolerated dose will be included in the trial.

The study participants will have the option to enter a long-term extension study, after completion of the treatment.

GRIN Therapeutics’ parent company Neurvati Neurosciences chief medical officer Michael Panzara said: “GRIN-related disorders represent a significant area of unmet need in healthcare, and the initiation of the Honeycomb Study is a historic milestone for GRIN Therapeutics and for patients around the world who are in desperate need of new treatments.

“We continue to be inspired by the children and families affected by GRIN-related disorders and by the leaders from the treatment community who have supported this important research and are very grateful for their partnership.”