MicuRx Completes Phase III Trial of MRX-4 Injection in China

Shanghai MicuRx Pharmaceutical Co., Ltd. (MicuRx) has announced the successful conclusion of its Phase III clinical trial of MRX-4 for injection, which transitions to oral Contezolid tablets for treating adult patients with complex skin and soft tissue infections (cSSTI) in China. The trial successfully met its primary efficacy endpoint, and the company plans to advance the New Drug Application (NDA) process for MRX-4 in China.

### Clinical Trial Outcomes and Insights

The clinical trial aimed to compare MRX-4 for injection transitioning to oral Contezolid tablets against intravenous Linezolid in treating cSSTI, including infections caused by methicillin-resistant Staphylococcus aureus (MRSA). The MRX-4 regimen involved an initial intravenous dose of 2000 mg, followed by 1000 mg doses, and subsequent oral administration of 800 mg Contezolid tablets every 12 hours for 7-14 days. The study demonstrated that MRX-4/Contezolid had effective clinical and microbiological efficacy, showing non-inferiority to Linezolid in clinical efficacy and achieving the trial's primary endpoint.

In terms of safety, MRX-4/Contezolid displayed good tolerability. There were no adverse events leading to treatment discontinuation or withdrawal. The most common adverse events were gastrointestinal issues such as nausea and vomiting. Laboratory tests showed mild and transient elevations in liver enzymes, and the incidence of platelet reduction and other hematological adverse events was lower in the MRX-4/Contezolid group compared to the Linezolid group.

### Study Implications and Future Directions

The success of this trial is anticipated to lead to the approval and commercialization of MRX-4 for injection in China, offering a new treatment option for critically ill patients and those who cannot take oral medication. This development is expected to meet significant clinical needs and boost MicuRx's revenue in the Chinese market. The company plans to continue investing in this project, complete communications with the Center for Drug Evaluation (CDE), submit the NDA, and undergo necessary technical reviews and site inspections.

Additionally, MicuRx is planning further clinical trials as part of its lifecycle management for oral Contezolid tablets and MRX-4 for injection. The company intends to conduct a Phase III trial in China to evaluate MRX-4/Contezolid tablets for treating infections caused by drug-resistant Gram-positive bacteria at various sites. This trial aims to expand the drug's potential applications and increase its social and commercial value. Furthermore, an international multicenter Phase III clinical trial for MRX-4/Contezolid tablets in treating diabetic foot infections is ongoing, with China participating as one of the trial sites.

### About Contezolid Tablets and MRX-4

Contezolid tablets and MRX-4 are novel antibacterial drugs in the oxazolidinone class, developed by MicuRx with global intellectual property rights. Contezolid tablets (400 mg) received approval from the National Medical Products Administration (NMPA) in China on June 1, 2021, for treating cSSTI, marking their first worldwide approval.

MRX-4 for injection is a water-soluble prodrug of contezolid, designed based on comprehensive analysis and scientific investigation of contezolid. Once administered, MRX-4 is converted into the active ingredient contezolid in the body, broadening its potential use cases.

### Conclusion

The successful Phase III clinical trial of MRX-4 for injection transitioning to oral Contezolid tablets marks a significant milestone for MicuRx, potentially paving the way for new treatment options for cSSTI in China. The resulting approval and commercialization efforts are set to enhance therapeutic options and benefit patients, while also contributing to MicuRx’s market presence and growth.