Pharmaceutical companies Santhera Pharmaceuticals and ReveraGen BioPharma have announced new data from their clinical study of a potential treatment for Duchenne muscular dystrophy (DMD) that could replace the current standard of care, corticosteroids.

Their investigational drug, Vamorolone, has the potential to slow disease progression in DMD in a similar way to corticosteroids, but with less severe side effects. Vamorolone was developed as a dissociative steroid, meaning that it may be able to chemically separate the clinical benefits of steroids from their safety concerns.

Duchenne UK and our charity partners, Joining Jack and the Duchenne Research Fund, together invested £750,000 into the development of Vamorolone. We are therefore pleased to see the latest positive data from Phase 2a of the clinical study.

48 boys with DMD were involved in the trial, aged from 4 – 10. These patients were .

The primary measure of the study was the Time to Stand test The latest results have shown that:

  • Patients receiving higher doses of Vamorolone improved their Time to Stand compared against patients on the lower doses. They also improved against results from steroid-naïve patients on the Natural History study conducted by the Cooperative International Neuromuscular Research Group (CINRG).
  • This improvement was an average of 0.05 rises per second, meaning that there was an improvement from 5 to 4 seconds, or from 8 to 5.7 seconds in the Time to Stand test.
  • This change was seen over 2.5 years when compared to the steroid-naïve patients from the Natural History study. This reduction in time to stand is the same as the effects of glucocorticoids seen in other studies.
  • A similar change was seen in the Time to Run/Walk 10 metres test, but there were not enough patients who completed the 6-minute walk test to enable a comparison.
  • The doses they received (2.0 and 6.0 mg/kg/day) were safe and well tolerated. Some patients experienced weight gain on 6.0mg/kg dose, but this reduced when the dosage was reduced. Other side effects associated with corticosteroids, such as cushingoid appearance (a rounded, puffy face) and behavioural changes, were only seen in a few patients. There were no reports of stunted growth, a common side effect of corticosteroids.

“We are very pleased with the results of this long-term follow-up which show that treatment benefits of Vamorolone are sustained over the 2.5-year follow-up period. Importantly, Vamorolone was well tolerated and we observed far fewer of the side effects typically seen with corticosteroids in the clinic,” said Eric Hoffman PhD, President and CEO at ReveraGen BioPharma. “We would like to thank all patients, their caregivers and health care professionals for their much-valued participation in these studies which, we are confident, will support our approach to develop Vamorolone as a novel treatment for this devastating disease.”

The six-month results from the Phase 2b study are expected to be released this Summer. This will be the definitive trial to test if Vamorolone is a potential treatment for DMD.

Vamorolone has been granted Orphan Drug status in the US and in Europe, and has Promising Innovate Medicine (PIM) status from the UK Medical and Healthcare products Regulatory Agency (MHRA). This may make it eligible for the Early Access to Medicines Scheme, which Duchenne UK has previously campaigned for.

You can read Sarentha and ReveraGen’s full press release here.