Rusfertide maintained haematocrit levels and reduced the need for phlebotomy, according to data from the company.
Early results from a phase 3 trial of rusfertide in polycythaemia vera patients suggests the hepcidin mimetic keeps haematocrit levels low and reduces the need for phlebotomies.
Patients with polycythaemia vera require regular phlebotomies and cytoreductive therapies to reduce their risk of cardiovascular and thrombotic events. These treatment approaches have a significant negative impact on quality of life due to the time demands and the associated adverse effects.
But a recent press release from Protagonist Therapeutics and Takeda Pharmaceuticals suggests polycythaemia vera patients may be one step closer to a novel therapy, with rusfertide, their hepcidin mimetic peptide, meeting all endpoints from the phase 3 VERIFY study.
“The totality of impressive clinical data to date shows that rusfertide has the potential for meaningful positive impact on the lives of patients with polycythaemia vera,” Protagonist’s president and CEO Dr Dinesh Patel (PhD) said in a statement.
“The study results also mark a critical inflection point in Protagonist’s decade-long journey in the hepcidin program and further validates our platform an expertise in innovating highly differentiated peptide-based medicines to fulfil unmet medical needs.”
As part of the trial, researchers recruited 293 phlebotomy-dependent patients with polycythaemia vera with uncontrolled haematocrit despite standard treatment. Patients received once-weekly subcutaneous injections of rusfertide or placebo.
At week 20-32 a greater proportion of rusfertide-treated patients were deemed to be “not phlebotomy eligible” – meaning they did not require a phlebotomy during this 12-week period as their haematocrit levels were below 45% – compared to placebo (77% versus 33%).
The four secondary endpoints – the average number of phlebotomies per patient, the proportion of patients with a haematocrit value <45 and self-reported changes in fatigue and myelofibrosis symptoms – were also met.
Dr Cavan Bennet (PhD), a senior research officer at the Walter and Eliza Hall Institute for Medical Research whose research work includes exploring novel treatments for polycythaemia vera, said the results were “very promising” and hoped FDA approval for rusfertide would be granted within the next two years.
“That will be a really big milestone for patients. Having worked with a lot of consumers, it will be fantastic if they are able to have a weekly or monthly injection instead of having to go for phlebotomies… it will be massive for those patients,” Dr Bennett told Haematology Republic.
No serious drug-related adverse events were reported during the VERIFY trial, with most of the events that did occur being grade one or two reactions at the injection site. Rusfertide-treated patients did not display an increased risk of cancer compared to those who received placebo.
Protagonist, the late-stage development biopharmaceutical company who co-developed rusfertide with Takeda, plans to submit their findings to regulatory agencies for approval in the near future. The FDA has already designated rusfertide with Orphan Drug and Fast Track status.
Dr Bennett noted there was still much to research once the haematological features of polycythaemia vera can be controlled through treatments such as rusfertide.
“I think there’s a need for new treatments to be able to combat the transformation to acute myeloid leukemia and myelofibrosis, and research can look at other features such as inflammation and the role of the bone marrow in disease,” he said.
