The pharma giant said it intends to submit concizumab for regulatory approval in the second half of 2022 in the US and Japan, and in 2023 in the EU and the UK.
Concizumab is an anti-TFPI monoclonal antibody, designed to block TFPI, the protein that stops blood from clotting. It is given as a once-daily prophylactic treatment, with administration under-the-skin for all types of hemophilia.
Some people with hemophilia may also develop inhibitors, which are an immune system response to the clotting factors in replacement therapy that cause the treatment to stop working. Currently, it is estimated that 30% of people living with hemophilia A and 1-3% of people living with hemophilia B have inhibitors.
The primary analysis of the findings of the explorer7 study of that drug were presented on June 10 at the International Society of Thrombosis and Haemostasis Annual Congress (ISTH 2022) in London, UK.
Results read-out
The results showed the primary endpoint was achieved, an 86% reduction in treated spontaneous and traumatic bleeds when on prophylactic treatment, and an estimated mean annualized bleeding rate (ABR) of 1.7 compared to 11.8 with no prophylaxis.
The overall median ABR of concizumab was zero, compared to 9.8 for no prophylaxis, said the Danish company.
Twenty-one (63.6%) people on concizumab experienced no treated bleeds, compared to two (10.5%) on no prophylaxis, it continued.
The safety and tolerability profile of concizumab in this study was within the expected range, with no thromboembolic events reported after treatment restart, it added.
“One of the most critical complications in the treatment of hemophilia is the development of inhibitors, as they render standard replacement therapy ineffective and severely limit treatment options for hemophilia B,” noted explorer7 lead investigator Dr Victor Jiménez-Yuste, Haematology Department, La Paz University Hospital, Madrid, Spain.
Earlier setback
The positive data readout comes over two years after the company paused its two clinical trials in phase 3 program and one study in the phase 2 program for concizumab as a result of the occurrence of non-fatal thrombotic events in three patients.
The US Food and Drug Administration (FDA) also placed the program on clinical hold.
However, in August of that year the pharma group said clinical trials in the concizumab phase 3 programs (explorer6, 7 and 8) had resumed.
Together with the relevant authorities, Novo said it had identified a “new path forward” for the drug, that new safety measures and guidelines, based on analysis of all available data, were agreed with the FDA and the clinical hold had subsequently been lifted.