Chinese biotech Innovent Biologics has been given approval by the FDA to start trials of an antibody that targets CD47, an emerging target in immuno-oncology.
Innovent can now start trials of IBI-188 in patients with advanced malignancies and lymphomas, says the biotech, and is the second of its pipeline drugs to be cleared for US trials after PD-1 inhibitor sintilimab (IBI-308) – partnered with Eli Lilly – got a green light earlier this year.
CD47 is a cell membrane receptor belonging to the immunoglobulin (Ig) superfamily, which is found on the surface of many tumour types and seems to protect against their destruction by the immune system by sending out a ‘don’t eat me’ signal to macrophage cells.
Studies have also suggested that blocking CD47 can send some tumour cells into programmed cell death (apoptosis), and the receptor seems to play a key role in the tumour microenvironment, affecting cell growth and migration and blood vessel formation. Some cancer cells express CD47 at very high levels and this seems to correlate with poor survival.
Sintilimab is being positioned initially for the Chinese market, given the wealth of competition in the PD-1/PD-L1 inhibitor category in the US and Europe. But with IBI-188, Innovent has a candidate that is in the running to be one of the first to market in a brand new I-O category worldwide – and a clear leader in China.
“CD47 … has become a highly researched therapeutic target across the world,” said the company in a statement, noting that there are a few CD47 programmes in phase 1 and 2 testing outside China.
Innovent is facing some well-positioned competition in the CD47 space. A US biotech – Stanford University spinout Forty Seven – is advancing a CD47-targeting antibody called Hu5F9-G4 in mid-stage trials, and has already attracted partnerships with Merck KGaA and Roche who are testing it alongside their checkpoint inhibitors.
Other companies working on CD47 antibodies include Canada’s Trillium Therapeutics – whose TTI-621 candidate is in early-stage testing – while US biotechs Arch Oncology and Aurigene and Synthon of the Netherlands have programmes in early development. And earlier this year Boehringer Ingelheim licensed a drug from French biotech OSE Immunotherapeutics that targets SIRP-alpha – which binds to CD47 – in a €1.1bn deal.
Meanwhile, Swiss biotech Novimmune is working on a bispecific antibody that targets CD47 and CD19. The rationale for that dual approach is that CD47 is widely distributed in healthy tissues, and targeting CD19 can help avoid potential ‘off-target’ effects by zeroing in on cancer cells. The candidate – acquired along with TH Therapeutics in June – is due to start clinical trials next year.
Innovent reckons IB-188 has stronger receptor blocking ability than other investigational drugs against CD47, and says it intends to start several clinical trials across multiple cancers, including non-Hodgkin’s lymphoma and ovarian cancer.
Meanwhile, Innovent is now waiting for a regulatory verdict from the Chinese medicines regulator for sintilimab, which was the drug domestically-developed PD-1 inhibitor to be filed for approval in China last December and came just a few weeks after Bristol-Myers Squibb submitted Opdivo (nivolumab).