resTORbio has commenced the Phase III PROTECTOR clinical programme to assess RTB101 to treat clinically symptomatic respiratory illness in elderly people.

RTB101 is an oral, small molecule, potent inhibitor of rapamycin complex 1 (TORC1).

The Phase III programme is designed to evaluate the safety and efficacy of the compound in subjects aged 65 and over.

It comprises two randomised, double-blinded, placebo-controlled clinical trials to study 10mg, once-daily RTB101 over 16 weeks during winter cold and flu season.

Dubbed PROTECTOR 1, the first trial in the programme is expected to enrol around 1,000 subjects.

“We believe this programme will provide us with sufficient clinical data to support the submission of an NDA.”

The second PROTECTOR 2 trial, which is set to begin in the fourth quarter of this year, will recruit nearly 1,600 participants. The trials will not include current smokers and chronic obstructive pulmonary disease patients.

Primary endpoint of the trials is a decrease in the proportion of clinically symptomatic respiratory illness patients with or without laboratory-confirmation of a pathogen.

The company expects to report top-line results from both trials in mid-2020.

resTORbio co-founder, president and CEO Chen Schor said: “The launch of our PROTECTOR Phase III programme is an important milestone for resTORbio and for the elderly population, as RTB101 has the potential to be the first immunotherapy for reducing the incidence of illness associated with RTIs, regardless of the causative pathogen.

“We plan to enrol approximately 2,600 subjects in our Phase III trials, and believe this programme will provide us with sufficient clinical data to support the submission of a new drug application (NDA) with the US Food and Drug Administration (FDA) for RTB101.”

In two Phase II trials involving more than 900 elderly patients, RTB101 demonstrated improvement in immune function via upregulation of antiviral gene expression, and also reduction in the respiratory tract infections (RTIs) incidence.