Breakthrough! China’s First Single-Agent 3CL Inhibitor, Leiretavir Tablets, Granted Conditional Approval

Guangzhou, China – March 23, 2023 – Guangdong Raynovent Biotech Co., Ltd. ("Raynovent") announced that Leiretavir tablets (brand name: LERUILING®), China’s first single-agent 3CL protease inhibitor, has received conditional approval from China’s National Medical Products Administration (NMPA) under the Special Review and Approval Procedure.

Leritrelvir is a Class 1 innovative anti-SARS-CoV-2 drug independently developed by the company with global intellectual property rights. It is a peptidomimetic inhibitor targeting the SARS-CoV-2 main protease (Mpro/3CLpro), preventing viral replication by inhibiting the cleavage of viral polyprotein precursors. Preclinical studies demonstrated potent antiviral activity against five major SARS-CoV-2 variants—wild-type, Alpha, Beta, Delta, and Omicron (including BA.1, BA.5, BF.7)—with efficacy comparable to Pfizer's nirmatrelvir (PF-07321332).

Approval was based on a randomized, double-blind, placebo-controlled Phase III trial in adult patients with mild-to-moderate COVID-19. A total of 1,359 participants aged 18–75 years, who tested positive for SARS-CoV-2 within 120 hours and had symptom onset within 48 hours prior to randomization, were enrolled. Patients received either Leiretavir (400 mg three times daily) or placebo orally for five days.

The primary endpoint was time to sustained clinical recovery from 11 target symptoms—defined as the interval from first dose until all symptoms normalized (score = 0) and remained so for at least three consecutive days. Leiretavir met the primary endpoint, significantly shortening recovery time versus placebo, and rapidly reducing viral load. Consistent benefits were observed across secondary endpoints, including higher rates of sustained recovery, shorter time to viral negativity, and greater viral clearance. The safety profile was comparable to placebo.

Notably, Leiretavir achieves robust efficacy as a single agent without ritonavir co-administration, avoiding associated clinical limitations and safety risks, thus offering a valuable option for elderly and comorbid patients ineligible for ritonavir-based regimens.

As China’s first domestically developed, single-agent 3CL inhibitor with full independent IP, Leritrelvir’s launch is expected to provide more treatment options for SARS-CoV-2 patients.

Dr. Chen Xiaoxin, Co-Founder and President of  Raynovent
"Raynovent was among the few domestic companies fully committed to advancing 3CL-targeted candidates even before Pfizer announced Paxlovid results. As a majority-owned subsidiary of Zhongsheng Pharmaceutical Group, we bear significant responsibility for the Group’s innovative pipeline. With strong government support, our team completed the journey from IND submission to conditional approval in under one year—a testament to our resolve and execution. I am immensely proud of our R&D team’s capabilities and dedication. We extend our deepest gratitude to all collaborators. Building on Leritrelvir’s success, we will continue innovating to address unmet public health needs."

Mr. Long Chaofeng, Founder and Chairman of Raynovent

"Raynovent is dedicated to addressing unmet clinical needs in respiratory and metabolic diseases. I am thrilled to witness the conditional approval of China’s first single-agent 3CL inhibitor. Our visionary, passionate R&D team achieved a series of milestones—from IND filing and Phase I trials to IITs and pivotal Phase III study—culminating in approval in under one year. This is nothing short of a miracle, showcasing extraordinary dedication and capability."