Candidate: PTC299

Type: Oral dihydroorotate dehydrogenase (DHODH) inhibitor with a novel dual-mechanism of action designed to address the high-viral replication and uncontrolled inflammatory response that ensues after COVID-19 infection.

Status: PTC said June 17th the FDA authorized a Phase II/III trial designed to evaluate PTC299 as a COVID-19 treatment. PTC plans to launch the integrated Phase II/III study in the U.S. “in the coming days,” with additional sites planned globally. The randomized, double-blind, placebo-controlled, multi-national study will be conducted in two stages—a first stage of 40 patients, followed by a larger cohort of approximately 340 patients. The trial’s primary objective is to evaluate the clinical efficacy of PTC299 compared with placebo assessed by time to respiratory improvement in adults hospitalized with COVID-19.

PTC said it agreed to advance PTC299 rapidly into the clinic after it showed broad-spectrum antiviral activity—specifically, potent inhibition of viral replication in SARS-CoV-2 cell-based assays.

PTC299 is also being developed for treatment in oncological indications, having been studied in nine clinical trials with more than 300 participants, including both oncology patients and healthy volunteers. PTC299 is also currently under study in a clinical trial in acute myeloid leukemia (AML) patients.

COVID-19: 200 Candidates and Counting

To navigate through the >200 potential therapeutic and vaccine options for COVID-19, GEN has grouped the candidates into four broad categories based on their developmental and (where applicable) clinical progress:

FRONT RUNNER – the most promising therapeutics/vaccines based on clinical progress, favorable data or both.

DEFINITELY MAYBE – earlier phases with promising partners, or more advanced candidates in development that have generated uneven data.

KEEPING AN EYE ON… – interesting technology, attracting notable partners, or both, but preliminary data.

TOO SOON TO TELL – longshots pending additional experimental and/or clinical data.

GEN has also tagged the most common treatment types:


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