Key inflection point: topline data readout from the PhaseOut DMD phase 2 trial in Duchenne (DMD) expected in 3Q 2018 Imminent start of a pivotal phase 3 study for ridinilazole in C. difficile infections (CDI) Recent Discuva acquisition reinforces novel antibiotics discovery capabilities Current valuation (market cap of c. $165 mln) undemanding given the stage and commercial potential of Summit's lead programs
DMD is an extremely severe genetic disease, affecting approximately 1:3500 male births. It is estimated that there are about 50,000 DMD patients in the US, European and Japanese markets.
Due to random mutations of the dystrophin gene, the dystrophin protein isn't synthetized and this causes a progressive degradation of the muscular tissue. Symptoms start to appear in the first years of life and typically DMD patients lose the ability to walk in their early teens, and ultimately die of respiratory or cardiac complications in their mid-twenties.
Mainstay drug treatment has long been limited to the chronic use of corticosteroids, until two new drugs were recently approved. Sarepta's Exondys 51 was launched in the US in 2017, whereas PTC's Translarna has been available in Europe since 2015. Both drugs only work in patients with specific genetic mutations, so each covers approx. 10-15% of the Duchenne population.
By contrast Summit's ezutromid may become a universal drug treatment, addressing all Duchenne patients. In developmental muscular fibres, the dystrophin's function is carried out by a similar protein called utrophin. Utrophin is then replaced by dystrophin as the fibres mature. Ezutromid is an oral drug that works by keeping the expression of utrophin switched on in the mature muscular tissue, thereby preventing its degradation. Summit has recently reported interim data from the ongoing phase 2 clinical trial, that is studying ezutromid in 40 patients, aged 5-10.
Interim muscle biopsy data from 23 patients, over 24 weeks, have shown a significant reduction of muscular damage. Figure 1 shows a patient's biopsy at baseline and week 24, when a lower repair activity is evident from the reduction of yellow, orange and red fibres.