Vico Therapeutics has dosed the first patient in a Phase l/lla trial of VO659 to treat Huntington’s disease (HD), spinocerebellar ataxia type 1 (SCA1) and type 3 (SCA3).

The Phase l/lla multi-centre, open label basket trial aims to evaluate the safety and tolerability of several ascending doses of VO659 given intrathecally to patients showing early signs of HD or mild to moderate SCA1 or SCA3.

Its exploratory endpoints are the review of pharmacodynamic biomarkers, including mHTT, total HTT, mATXN3, total ATXN3 and neurofilament light chain, in cerebrospinal fluid, plasma pharmacokinetics as well as clinical outcome measures.

The trial intends to include around 71 patients.

Vico Therapeutics chief medical officer Scott Schobel said: “VO659 is the first allele-preferential ASO in clinical development with broad application to all CAG repeat expansion diseases.

“The robust preclinical data package for VO659 demonstrates favourable brain uptake, potency and durability of effect, and we look forward to assessing the translation of these characteristics in this clinical trial.”

VO659 is an antisense oligonucleotide (ASO) therapy that is currently under investigation for targeting the CAG repeat expansion that causes nine polyglutamine diseases including HD, SCA1 and SCA3.

Results from preclinical study revealed that VO659 was capable of significantly minimising mutant ATXN1 (mATXN1) and mutant ATXN3 (mATXN3) protein levels in vivo and in vitro in disease mouse models, along with patient cell models of SCA1 and SCA3, respectively.