Traws Pharma Advances Oral COVID-19, Monthly Flu Antiviral Toward Next Milestones

Traws Pharma Inc. (NASDAQ:TRAW) announced final Phase 2a clinical data for its investigational oral COVID-19 therapy ratutrelvir alongside completed bridging and toxicology studies for its once-monthly influenza candidate, tivoxavir marboxil.

Ratutrelvir Matches Paxlovid Efficacy With Fewer Side Effects

The clinical-stage biopharmaceutical company evaluated ratutrelvir, a ritonavir-free Mpro/3CL protease inhibitor, in 92 patients with mild-to-moderate COVID-19.

In a randomized arm of 62 patients eligible for Paxlovid, subjects received either 600 mg of ratutrelvir once daily for 10 days or Paxlovid for five days.

Ratutrelvir achieved a median time to sustained symptom resolution of 13.5 days, compared with 14.5 days for Paxlovid.

Both treatments reduced nasal viral RNA at similar rates, and neither group showed virologic rebound through Day 28.

Only one of 32 ratutrelvir patients experienced treatment-related adverse events, versus four of 30 Paxlovid patients.

Traws also tested ratutrelvir in 30 older patients with high cardiovascular and pulmonary comorbidities who could not take Paxlovid due to drug interactions.

These patients cleared the virus at a comparable rate, resolved symptoms in 14 days, and reported zero treatment-related adverse events.

FDA Discussions and Once-Monthly Influenza Progress

Traws plans to meet with the FDA to map out a registration path for high-risk COVID-19 adults ineligible for Paxlovid, including a potential adaptive Phase 2b/pivotal trial and Fast Track designation.

Separately, the company completed an Australian healthy-volunteer bridging study under an open investigational new drug application for a compressed tablet formulation of tivoxavir marboxil.

The well-tolerated tablet matched powder-in-capsule drug exposure, supporting once-monthly dosing and a planned human influenza challenge study.

Finally, Traws finished retesting tivoxavir marboxil in two independent rat gene mutation assays.

Researchers observed no bone marrow cell mutations up to 500 mg/kg — a 125-fold safety margin over planned clinical exposure — while seeing effects at 2,000 mg/kg and inconsistently at 1,000 mg/kg.

Traws expects to resubmit the updated toxicology package to regulators in the fourth quarter of 2026.

TRAW Price Action: Traws Pharma shares were up 17.96% at 29 cents at the time of publication on Thursday. The stock is trading near its 52-week low of 21 cents, according to Benzinga Pro data.

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