Jan 29, 2019, /EqualOcean/ - I-Mab-Biopharma (天境生物), a biopharmaceutical research and development company located in Shanghai, focusing on tumor treatment and autoimmune diseases, announced its independently developed CD47 targeted human monoclonal antibody TJC4 was approved by the US Food and Drug Administration (FDA) for clinical research on January 25, 2019 (US Eastern Standard Time).

TJC4 is the third drug approved by the FDA for clinical research within one month of application. The company claimed unlike other known CD47 targeted antibodies, TJC4 has a unique paratope, which is also called as a binding site, that binds itself to red blood cells to a minimum extent, also does not cause cell condensation, and no anemia symptoms occur during toxicology experiments using cynomolgus monkeys as samples. In addition, the antibody appears to be effective in both monotherapy and combination therapy in animal models of hematologic malignancies and solid tumor malignancies.

Dr. SHEN Huaqiong (申华琼), president of I-Mab Biopharma's R&D center said: "US FDA's approval for clinical research of TJC4 has significant meaning for further global research and development of I-Mab Biopharma's drug candidate." He also stated that "We believe TJC4's safety feature reflected in toxicology studies is a key advantage against other CD47 targeted antibodies also under development globally. TJC4 also unveils the possible optimizations in future tumor treatments.”

I-Mab Biopharma received 4 rounds of financing after its incubation since 2016, receiving more than USD 380,000,000 altogether. It also took Tasgen (天视珍生物) in March 2017, which is a company focusing on autoimmune diseases previously. According to ITJUZI.com, the company was backed by big investors like Hillhouse Capital (高瓴资本) and CDH Hund (鼎晖资本), who had history of extensively investing on healthcare companies in the past.

More efforts to be made after approval

Following the approval of the clinical trial, I-Mab Biopharma will fully launch the 1/1b clinical trial to assess the safety and explore the dosage, as well as to observe the effectiveness of TJC4 antibodies in patients with solid and lymphoma tumors in both monotherapy and combination therapy. This phase of research typically would last for several months, in which normally 20 to 100 healthy volunteers or people with the condition will be involved. About 70% of the drug candidates undergoing these research would be able to move to the next phase of the clinical trial. It is expected that by the second quarter of 2019, I-Mab Biopharma will be able to launch several clinical trial sites in the United States.

According to FDA's regulations, in order to launch the selling of the drugs developed, pharmaceutical companies need to fill a marketing application after the clinical trial ends, in which the drug developer must have "adequate data" from two large, controlled clinical trials. So that, opening more clinical trial sites would help the company to get more accurate data; multiple trials would also reveal more possible issues in terms of side effects and adverse reactions of the drug being examined, which aids the company to react prior to the final FDA review to prevent and improve the drug's effectiveness.  

The "Trial" has just begun

This is indeed an important step for I-Mab Biopharma to bring innovative drugs of high potential to patients around the world, nevertheless, this is also only the third step of the entire FDA drug approval phase, which includes 5 steps altogether. Except the last step, Post-market safety monitoring, the clinical research as well as the 4th step of FDA Review together could last for more than 4 years. The FDA Review stage alone needs 6-10 months for them to conduct complicated reviews and examine the report based on the developer's trial data. FDA sometimes also requires the developer to address questions based on trial data or even requires additional studies. This is not an easy journey to go through. After all, only 6.93% of all the drug candidates under review by FDA can end up in the market eventually.

A market full of beginners

According to PMGroup's research, CD47 is recognized as a hot research area by many Chinese biopharmaceutical companies recently, there are only a few CD47 developing programs under initial testing stages outside of China. ThermoFisher Scientific and abcam are offering a series of antibodies including monoclonal and polyclonal ones, but all are still for research use only. Also, Stanford University spinout Forty Seven leads in the R&D of CD47-targeting antibody and has already attracted attention from pharmaceutical giants like Merck KGaA and Roche, but still under clinical trial, and it may still need quite a few years for it to be seen in pharmacies. Apart from these, some biopharmaceutical companies are also developing CD47-targeting antibodies but are still at very initial stages, including Canada's Trillium Therapeutics, US biotechs Arch Oncology, Aurigene, and Synthon of the Netherlands.

What's worthwhile to be mentioned is Innovent (信达生物制药), a Chinese competitor for I-Mab Biopharma, who went to IPO in October last year; Its CD47-targeting antibodies were approved by FDA in the same month, and also claimed to have stronger receptor blocking ability than other antibodies under scrutinization against CD47. This claim somewhat resembles the ones made by I-Mab Biopharma. Studies have also suggested that blocking of CD47 can send some tumor cells into programmed cell death, therefore, to secure the healthy cells from infected tumor cells seem to be extremely important for tumor treatment. Not only these two companies, but many other biopharmaceutical companies in the future will also pay much attention on this field. The blocking ability of antibodies will also go through a series of upgrade and improvement, which requires continuous R&D for biopharmaceutical companies. In a word, the battle between biopharmaceutical companies in finding the best monoclonal antibodies in cancer treatment is still at its infancy, and the ultimate cure for cancer still awaits far ahead.