Dover, Delaware -- Expert Systems Inc., a leading life sciences accelerator, Supports Traws Pharma Phase 2 Clinical Studies of Ratutrelvir -- a Novel Ritonavir-Free Antiviral for COVID-19.

Rhea-AI Summary

Expert Systems Inc said it continues supporting Traws Pharma (NASDAQ: TRAW) as Traws begins Phase 2 trials of Ratutrelvir (TRX01), a ritonavir-free oral antiviral for newly diagnosed COVID-19 patients.

Key disclosed facts: Phase 1 MAD showed a 600 mg daily regimen sustaining plasma levels ~13× EC50 for a 10-day course with troughs above EC90. Regulatory clearance for Phase 2 was granted in Q3 2025. The Phase 2 program includes a non-inferiority trial vs PAXLOVID and a single-arm trial in PAXLOVID-ineligible patients. Expert Systems' AI-driven modeling contributed to PK and safety optimization and predicts higher lung tissue exposure.

Positive

• Phase 2 initiation after regulatory clearance in Q3 2025
• Phase 1 PK: 600 mg daily produced ~13× EC50 sustained over 10 days
• Ritonavir-free formulation avoids metabolic boosting and ~20% drug-interaction exclusions
• Phase 2 includes a non-inferiority trial versus PAXLOVID

Negative

• No human efficacy data yet; Phase 2 efficacy remains unproven
• Single-arm trial in PAXLOVID-ineligible patients limits direct comparative evidence

Insights

Clinical Pharmacology & Translational Medicine Expert

Phase 2 start after favorable Phase 1 PK/safety; ritonavir-free profile targets an excluded patient segment.

Expert Systems' AI-driven optimization produced Ratutrelvir (TRX01) with a reported daily 600 mg regimen that sustained plasma levels ~13× above EC50 across a 10-day course, with troughs above EC90. The drug's ritonavir-independent formulation avoids the ritonavir-associated drug-drug interactions said to exclude ~20% of patients, potentially broadening eligibility compared with boosted protease inhibitors.

Key dependencies and risks rest on confirmatory efficacy and safety in human disease. The program advanced to Phase 2 after Phase 1 safety and PK, and regulatory clearance to begin Phase 2 occurred in Q3 2025. The Phase 2 plan includes a non-inferiority trial versus PAXLOVID® and a single-arm study in PAXLOVID®-ineligible patients; those trials will determine whether the in vitro potency and plasma/lung exposure translate to clinical benefit.

Watch for interim efficacy signals and safety readouts from the Phase 2 trials and any pharmacokinetic-pharmacodynamic linkage showing sustained viral suppression and reduced rebound over the 10-day course; expect these milestones over the coming clinical readout windows following enrollment and dosing completion in 2025–2026.

DOVER, Del., Oct. 22, 2025 /PRNewswire/ -- Expert Systems Inc., a leading life sciences accelerator, announced its continued support for Traws Pharma (NASDAQ: TRAW) as the company initiates Phase 2 clinical studies of Ratutrelvir (TRX01), a next-generation oral antiviral designed to treat newly diagnosed COVID-19 patients.

Expert Systems' predictive pharmacology and AI-driven molecular modeling played a central role in Ratutrelvir's differentiation—optimizing pharmacokinetics, safety, and potency profiles to ensure broad clinical applicability across both therapeutic and preventive settings.

Ratutrelvir (TRX01) demonstrates broad-spectrum in vitro activity against a range of SARS-CoV-2 virus strains and maintains exceptional potency profiles without requiring ritonavir co-administration. Its ritonavir-independent formulation eliminates the need for metabolic boosting, avoiding the ritonavir-associated drug-drug interactions that currently exclude approximately 20% of COVID patients from protease inhibitor treatment.

In Phase 1 multiple ascending dose (MAD) studies, a daily oral 600 mg regimen sustained plasma concentrations ~13× above EC₅₀ for the full 10-day course, with trough levels remaining above EC₉₀  - critical for preventing viral rebound. Expert Systems' modeling predicts even higher concentrations in lung tissue versus plasma, enhancing antiviral exposure at the primary infection site..

Following successful completion of Phase 1 safety and PK studies, regulatory approval was granted for Phase 2 initiation in Q3 2025. The Phase 2 program includes:

• A non-inferiority trial versus PAXLOVID® in newly diagnosed COVID-19 patients; and
• A single-arm trial in PAXLOVID®-ineligible populations—an underserved group at greater risk for severe outcomes.

"COVID-19 continues to pose a significant public health threat, particularly among elderly and immunocompromised individuals who often cannot access current standard-of-care options," said Dr. Tudor Oprea, CEO of Expert Systems Inc. "By applying our AI/ML-driven molecular design platform to systematically optimize both potency and pharmacokinetics without ritonavir, we enabled the development of a truly differentiated antiviral. Ratutrelvir's superior 13× EC₅₀, ritonavir-free exposure, for an extended 10-day regimen, and excellent safety profile collectively exemplify precision drug design, targeting not only active infection but also the prevention of viral rebound and Long COVID."

Expert Systems will continue to provide strategic, scientific, and technological support as Ratutrelvir advances through human efficacy studies. This collaboration underscores Expert Systems' capability to apply computational design and predictive pharmacology to de-risk innovation and accelerate clinical translation of best-in-class therapeutics.

About Expert Systems Inc.

Expert Systems Inc. is a life sciences accelerator advancing the next generation of precision therapeutics. Its AI/ML-enabled platform integrates rational drug design, predictive pharmacology, translational modeling, regulatory strategy, and partnering support across the biotech value chain.

With a proven record of creating and scaling multiple Seed and Series A ventures, Expert Systems has supported more than 30 R&D programs funded by institutional investors and strategic partners across North America, Europe, and Australia. By shortening timelines from in silico discovery to first-in-human trials, Expert Systems transforms high-potential science into investable, clinically ready opportunities.

Media Contact:
Bill Farley, CBO
Expert Systems Inc.
bfarley@expertsystems.inc  

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SOURCE Expert Systems, Inc.

FAQ

What did Traws Pharma (TRAW) announce about Ratutrelvir on October 22, 2025?

Traws began Phase 2 studies of Ratutrelvir (TRX01) after Phase 1 showed PK supporting a 600 mg daily, 10-day regimen and regulators cleared Phase 2 in Q3 2025.

What Phase 1 pharmacokinetic result supports Ratutrelvir (TRAW) dosing?

Phase 1 MAD data reported a 600 mg daily regimen sustaining plasma concentrations ~13× EC50 with troughs above EC90 for the full 10-day course.

How does Ratutrelvir (TRAW) differ from PAXLOVID in formulation?

Ratutrelvir is described as ritonavir-free, eliminating the need for metabolic boosting and avoiding ritonavir-associated drug-drug interactions that exclude about 20% of patients.

What trials are included in the Ratutrelvir Phase 2 program for TRAW?

The Phase 2 program includes a non-inferiority trial versus PAXLOVID in newly diagnosed patients and a single-arm trial in PAXLOVID-ineligible populations.

Does the October 22, 2025 announcement report clinical efficacy of Ratutrelvir?

No; the announcement reports PK and safety from Phase 1 and initiation of Phase 2 but does not report Phase 2 efficacy results.

What role did Expert Systems Inc play in Ratutrelvir's development for TRAW?

Expert Systems provided AI-driven molecular modeling and predictive pharmacology to help optimize Ratutrelvir's pharmacokinetics, safety, and potency profiles.