A strong FDA panel vote in favour of the Clostridium difficile antibiotic Dificid (fidaxomicin) signals that Optimer Pharmaceuticals’ optimistic view of its chances of making it to the market is warranted. The unanimous backing of its safety and efficacy was followed in close order by a co-promotion deal with Cubist Pharmaceuticals, itself fresh off a positive patent settlement with Teva over Cubicin (Cubicin patent settlement brightens Cubist's future, April 5, 2011).
The main challenge facing the two anti-infectives specialists now will be justifying Dificid’s costs, expected to be many times that of currently used drugs, to hospital pharmacy committees. The deal with Cubist has the potential to speed uptake and avert some of the costs of a solo launch.
Take your marks
Optimer shares were down 6% to $12.98 in early trading today. That might be a surprise given that the $838m net present value of Dificid exceeds Optimer's $637m market capitalisation, according to EvaluatePharma data. However, the drop is likely a reflection that a positive vote was widely expected, with shares having risen 17% since advisory committee briefing documents were released on Friday.
And with final FDA approval now likely, and Optimer already signing up US and European partners, few near-term catalysts for the stock remain.
With $174m in cash accumulated following a European partnership with Astellas Pharma and a public offering in February, Optimer is readying for a launch in August following an FDA decision expected by the May 30 PDUFA deadline (Event - Partnership a prelude to regulators' judgement for Optimer, Febuary 8, 2011). In a call with investors today, chief executive Pedro Lichtinger said the company is starting to build its field force of 100 reps immediately, which will join Cubist's sales reps marketing its antibiotic Cubicin.
The initial strategy will be marketing to the 1,100 US hospitals with 75% of the reported cases of C. difficile, which may number at 300,000 or more. The priority will be to demonstrate that a 10-day course of Dificid is a better value than competitors Vancocin, metronidazole or the inexpensive oral vancomycin slurry, the latter being a relatively new treatment for C. difficile related diarrhoea.
Analysts from Bank of America-Merrill Lynch estimate the Dificid course at $2,000, compared with $1,000 for Vancocin, $200 for vancomycin slurry and $50 for metronidazole. Mr Lichtinger said the company is preparing to publish data demonstrating Dificid’s cost effectiveness, which he said has “clear value.”
“I’m not saying this will be easy because the cost-containment environment is difficult,” he said. But he added, “It will have a fact-based clear economic benefit to all of the stakeholders.”
While the US panel gave a unanimous vote in favour of Dificid’s safety and efficacy as compared to vancomycin, the experts split their vote, 6-6, on the clinical significance of a lower recurrence of C. difficile related diarrhoea at day 31.
Inclusion of that claim on product marketing would clearly give Dificid a marketing edge in what is already a competitive market – and one that will be increasingly competitive as Vancocin copycats hit the market, possibly as soon as this year (ViroPharma can finally look forward after losing Vancocin battle, August 5, 2009).
Mr Lichtinger said the company expects, however, that language alluding to the 31-day recurrence data will make its way onto the label or product information, but acknowledged that the word “recurrence” is not likely to be there: “It will be a different word. We will work with the FDA to find that word.”
The two-year deal with Cubist essentially buys a ready-made sales force already marketing antibiotics in hospitals - the terms of the deal include a $15m annual service fee and additional fees if sales targets are met. The price equals a sales force of around 50-75 representatives, and should help Optimer in its second target of reaching 2,000 hospitals, or over 90% of C. difficile cases in US hospitals.
The limited term of the deal also reduces the potential of competition from Cubist’s own phase II C. difficile product, CB-183,315, depending on whether it clears clinical and regulatory review, Mr. Lichtinger said.
Dificid looks to be well-clear of clinical questions and heading for regulatory approval. The question now is how well it will compete.