Brii Bio Announces Strategic Partnership with China Resources Pharmaceutical Commercial Group to Advance the Commercialization of Long-acting COVID-19 Neutralizing Antibody Therapy, Amubarvimab/Romlusevimab Combination, in China

The partnership will accelerate stockpiling,channel distribution and hospital access for the amubarvimab/romlusevimabcombination in China

The amubarvimab/romlusevimab combination is the first locally-discovered and approved SARS-CoV-2 target-specific treatment in China,evaluated through a randomized,double-blind,placebo-controlled trial

The amubarvimab/romlusevimab combination was commercially launched in China on July 7,2022

DURHAM,N.C. and BEIJING,July 19,2022 --Brii Biosciences Limited ("Brii Bio" or the "Company",stock code: 2137.HK) a multi-national company developing innovative therapies for diseases with significant unmet medical needs and large public health burdens,today announced that TSB Therapeutics (Beijing) Co.,Ltd. ("TSB Therapeutics"),a joint venture majority-owned by the Company,is partnering with China Resources Pharmaceutical Commercial Group Co.,Ltd. ("CR Pharma Comm")to advance stockpiling,channel distribution and hospital access for the Company's long-acting neutralizing monoclonal antibody (mAb) therapy,the amubarvimab/romlusevimab combination. The two parties are working together to ensure timely drug supply that supports the COVID-19 pandemic prevention and control efforts in China. The collaboration will also explore other novel partnership opportunities to enable expanded access of the combination therapy in China.

On December 8,2021,the National Medical Products Administration (NMPA) of China approved the amubarvimab/romlusevimab combination for the treatment of adults and pediatric patients (age 12-17 weighing at least 40 kg) with mild and normal type of COVID-19 at high risk for progression to severe disease,including hospitalization or death. The indication of pediatric patients (age 12-17 weighing at least 40 kg) is under a conditional approval. On March 15,2022,the National Health Commission of China added the amubarvimab/romlusevimab combination to its COVID-19 Diagnosis and Treatment Guidelines (9th Pilot Edition) for the treatment of COVID-19. On July 7,the amubarvimab/romlusevimab combination was made commercially available in China.

"As the COVID-19 pandemic continues to impact the health of communities worldwide,we are proud to bring the amubarvimab/romlusevimab combination to patients in urgent need in China,and pleased with the 27-month timeline on which we were able to expedite this important work," said Rogers Luo,President and General Manager,Greater China of Brii Bio,and Chief Executive Officer of TSB Therapeutics. "In 2019,BriiBio started a strategic partnership with China Resources Group to jointly build an integrated industrial chain of life sciences. CR Pharma Comm is a large-scale pharmaceutical distribution enterprise owned by China Resources Pharmaceutical Group,which has an extensive drug marketing and channel distribution network. This strong and strategic partnership and uniqueoperating model enables Brii Bio to rapidly expand access to our amubarvimab/romlusevimab combination to help more COVID-19 patients in China,and we look forward to exploring in-depth collaborative efforts with China Resources Pharmaceutical Group down the line for the long-term benefit of patients and the healthcare community."

"We are thrilled that this important combination therapy is now commercially available as part of China's COVID-19 pandemic prevention and control strategy,enabling the treatment to quickly reach a much greater number of patients and provide meaningful clinical benefit to those in need. Brii Bio's success developing this combination therapy highlights the scientific innovation and infectious disease expertise coming out of the China biotechnology space," said Hong Mu,Chairman of CR Pharma Comm. "China Resources Group is a state-owned enterprise with an 83-year history of confronting profound healthcare risks and challenges,including those seen with the COVID-19 pandemic. CR Pharma Comm will work together with our subsidiaries across the country to fight on the front line,actively respond to the national strategy,strongly assist the government in stockpiling for emergency use,provide sufficient pharmaceuticals and medical equipment to medical institutions for pandemic prevention and control,ensure peoples' safety with timely medications,and practice the mission and undertaking of CR Pharma Comm."

On July 9,through the joint efforts of Brii Bio and CR Pharma Comm,the first batch of the combination therapy was successfully delivered to the Third People's Hospital of Shenzhen,and the first patient was dosed. From May to December 2021,Brii Bio donated nearly 3,000 doses of the amubarvimab/romlusevimab combination for emergency use in 22 hospitals in 21 cities as part of its commitment to ensure humanitarian access and to help curb the outbreaks of the pandemic. Nearly 1,000 patients received the treatment of the combination therapy. These real-world data provide important clinical application and safety data in China. The subsidiaries of CR Pharma Comm made a great contribution in delivering the drugs to the hospitals for clinical treatment of patients.

With the commercialization of the amubarvimab/romlusevimab combination,the Company will actively cooperate with its business partners,make every effort to improve accessibility,and advance drug stockpiling at all levels,to quickly respond to the sudden outbreak of COVID-19 and protect peoples'lives.

About Amubarvimab/Romlusevimab Combination

Amubarvimab and Romlusevimab are non-competing SARS-CoV-2 monoclonal neutralizing antibodies derived from convalesced COVID-19 patients developed in collaboration with the 3rd People's Hospital of Shenzhen and Tsinghua University. They have been specifically engineered to reduce the risk of antibody-dependent enhancement and prolong the plasma half-lives for potentially more durable treatment effect.

Based on the final results from the U.S. National Institutes of Health (NIH)/National Institute of Allergy and Infectious Diseases (NIAID)-sponsored ACTIV-2 Phase 3 clinical trial with 837 enrolled outpatients,the amubarvimab/romlusevimab combination demonstrates a statistically significant 80% reduction of hospitalization and death with fewer deaths through 28 days in the treatment arm (0) relative to placebo (9),and improved safety outcome over placebo in non-hospitalized COVID-19 patients at high risk of clinical progression to severe disease. Similar efficacy rates were observed in participants initiating therapy early (0-5 days) and late (6-10 days),following symptom onset,providing critically needed clinical evidence in COVID-19 patients who were late for treatment.

The live virus testing data,as well as pseudovirus testing data from multiple independent labs,have demonstrated that the amubarvimab/romlusevimab combination retains activity against major SARS-CoV-2 variants of concern,including the following commonly identified variants,B.1.1.7 (Alpha),B.1.351 (Beta),P.1 (Gamma),B.1.429 (Epsilon),B.1.617.2 (Delta),AY.4.2 (Delta Plus),C.37 (Lambda),B.1.621 (Mu),B.1.1.529-BA.1 (Omicron),and BA.1.1 and BA.2 (Omicron subvariants). Additional testings including live virus assays are being conducted to confirm the neutralizing activity against BA.4/5 and BA.2.12.1.

About Brii Bio

Brii Biosciences Limited ("Brii Bio",stock code: 2137.HK) is a biotechnology company based in China and the United States committed to advancing therapies for significant infectious diseases,such as hepatitis B,COVID-19,human immunodeficiency virus (HIV) infection,multi-drug resistant (MDR) or extensive drug resistant (XDR) gram-negative infections,and other illnesses,such as the central nervous system (CNS) diseases,which have significant public health burdens in China and worldwide. For more information,visit www.briibio.com.

About TSB Therapeutics

TSB Therapeutics (Beijing) Co.,Ltd. ("TSB Therapeutics") is a holding company of Brii Bio. TSB Therapeutics was jointly established in Beijing in May 2020 by Brii Bio,the 3rd People's Hospital of Shenzhen and Tsinghua University. The Company is committed to developing the amubarvimab/romlusevimab combination. TSB Therapeutics holds exclusive rights to develop and commercialize the amubarvimab/romlusevimab combination in Greater China.

About CR Pharma Comm

China Resources Pharmaceutical Commercial Group Co.,Ltd. ("CR Pharma Comm") is a large-scale pharmaceutical distribution enterprise wholly owned by China Resources Pharmaceutical Group and is one of the operations under the Healthcare business segment of China Resources Pharmaceutical Group. CR Pharma Comm is principally engaged in the marketing,distribution and delivery of pharmaceutical products and provision of pharmaceutical supply chain solutions,mainly covering chemical drug products,chemical APIs,Chinese proprietary medicines,herbal decoction pieces,medical devices,medical consumables,biologics,dietary supplements and others. CR Pharma Comm is one of the first pharmaceutical enterprises that obtained the GSP certification in China and holds the qualifications for the import and export of drugs and medical devices and third-party pharmaceutical logistics services. CR Pharma Comm maintains stable long-term cooperation with nearly 10,000 pharmaceutical manufacturers in China and overseas,and with Beijing as the center,has established a sales and marketing network covering 31 provinces and municipalities across China,mainly serving medical institutions of various levels,pharmaceutical wholesalers and retail pharmacies in China. CR Pharma Comm ranks the top 3 among the pharmaceutical commercial enterprises in China in terms of the business scale. CR Pharma Comm is active in acquiring high-quality domestic pharmaceutical distribution enterprises,and has formed a management and control system consisting of the headquarters,regional branches and commercial branches in a short period of time and has established a network covering the whole nation. To date,CR Pharma Comm has over 350 branches and subsidiaries in 28 provinces (including autonomous regions and municipalities) in China,and most of its subsidiaries have regional competitive advantages in the provinces,prefectures and cities where they operate.