First Patient Dosing achieved in Mainland China in a Phase II Multi-regional clinical trial (MRCT)

SHANGHAI,Oct. 12,2018 --I-Mab Biopharma ("I-Mab"),a company focusing on innovative biologics in immuno-oncology and immuno-inflammation,today announced thatthe first patientinmainland Chinahas been dosed in a phase II clinicaltrial ofTJ301forthe treatment ofulcerativecolitis (UC)attheDivisionofGastroenterology,theFirst Affiliated HospitalofSunYat-senUniversityin Guangdong,China.

TJ301 isa phase II,randomized,double-blind,placebo-controlled studyconducted in multiple sites among Mainland China,South Korea and Taiwan areato evaluate the safety and efficacy of TJ301 administered intravenously inpatients with active ulcerative colitis.

TJ301 is a selective IL-6 blocker. It works through a novel trans-signaling mechanismwithout interacting with either IL-6 or IL-6R individually. This mechanism of action is unique and different from other anti-IL6 or anti-IL6R productsthatblockall actions ofIL-6. TJ301 is expected to have a better safety profile as compared to the existingIL-6-basedbiologics.Through a licensing agreement with Ferringat the end of2016,I-Mabholdsexclusive rights to TJ301for further development and commercialization inGreaterChina andSouth Korea.

UlcerativeColitis (UC) is a chronic inflammatory bowel disease whose etiology and pathogenesis are unknown. Common clinical symptoms are diarrhea,bloody stools and abdominal pain. Although there are no definitiveepidemiological data available for MainlandChina,it is believed thatthe incidence of UC is about 11/100,000.At present,theclinical management of the disease in Mainland China mainly involves glucocorticoids and 5-aminosalicylic drugs.

"UC represents a significant unmet medical need in MainlandChina. We are thrilled to test this investigational medicine in the current clinical study whichhasalreadyenrolled a number of patients inTaiwan and South Korea and now the first patient in Mainland China. It is always our goal to provide better medicines through new drug discovery and development," saidDr. Joan Shen,Head of R&D.

AboutI-Mab

Facilitated by a merger between Third Venture Biotech andTasgenBio,which was followed by a Series B financing of USD 150 million in 2017,I-Mab has rapidly built a highly experienced team with world-class R&D capabilities. On June 29,2018,I-Mab announced that it hadsuccessfully raised US$220 million in Series C financing with a group of reputable investors led byHonyCapital,representing one of the largest amounts ever raised in Series C by an innovative biotech company in China.

I-Mab focuses on discovery and development of First-in-Class and Best-in-Class biologics in the areas of immuno-oncology and immuno-inflammation. The company has already initiated a Phase 2 clinical trial and is prepared to submit multiple IND applications for additional clinical trials in China and the US,including Phase 2 and Phase 3 studies.www.i-mabbiopharma.com.

Contact: i-mabclinical@i-mabbiopharma.com