Sometimes being good and meeting the expectations of everyone just is not enough. This was something that Trius Therapeutics discovered yesterday when it managed to prove that its antibiotic drug tedizolid (TR-701 IV) was non-inferior to Pfizer’s Zyvox in a second pivotal trial for treating acute bacterial skin and skin structure infections (ABSSSI).
With so many failures of antibiotics in late stage trials, passing the non-inferiority test has almost certainly guaranteed approval, which is why it was surprising shares in the San Diego-based group were flat following the news. What seems to have curtailed any wild celebrations and rocketing share price is the potential difficulties that Trius will face actually getting the drug onto hospital pharmacy shelves and the looming threat of generic Zyvox.
Non inferiority complex
The Establish-2 trial compared TR-701 to Zyvox; patients were intitally administered the drug intravenously and were switched to oral formulations (Event – Trius hopes tedizolid success is infectious, March 8, 2013). Yesterday, Trius announced that TR-701 IV had met both its primary endpoint of 20% decrease in lesion area at 48-72 hours, along with key secondary endpoints of sustained clinical response at the end of therapy and investigators' assessment of clinical response 7-14 days at the end of therapy.
Despite the market reaction the drug remains on track for a filing in the second half. It has been assured accelerated review by the FDA thanks to its Qualified Infectious Disease Product status. With the paucity of new antibiotics coming onto the market, as large drug makers have retreated from the space, it should have a good chance of approval and launch by the middle of 2014.
Getting fast sales
If approved the drug could do well against Zyvox, as not only does it have a once daily oral and IV dosing schedule, the treatment duration is also shorter than the Pfizer drug, with dosing over six days compared with 10. Tedizolid also has fewer GI side effects, one of the big limitations with Zyvox, and has also shown to have less of an impact on lowering patients’ platelet counts.
But tedizolid’s window of opportunity might be a very small one. Zyvox is due to lose patient protection in 2015, and even faced with a better tolerated alternative physicians and payers might pick the cheaper version. Trius also has to contend with the fact that it will take some time to get the drug into the formulary of hospitals, a process that will cut into the time it has without generic competition, one of the reasons why the shares might have fallen.
Additionally, while the company does have healthy cash reserves, launching and marketing tedizolid will considerably eat into these so, the drug needs to makes sales and fast while it can. Current forecasts for tedizolid are $217m in 2018, according to EvaluatePharma.
To contact the writer of this story email Lisa Urquhart in London at firstname.lastname@example.org or follow @LisaEPVantage on Twitter