Vertex’s cystic fibrosis combo, Orkambi, hasn’t exactly torn up the market since hitting the scene in 2015. Now, though, the company has a new combo prospect it hopes can fare better—but the question is, how much?
Earlier this week, the Massachusetts drugmaker unveiled positive top-line phase 3 results in homozygous delF508 and residual function patients for candidate tezacaftor in tandem with ivacaftor, a compound already approved on its own as Kalydeco.
Two trials met their primary and most secondary endpoints “resoundingly,” as Leerink Partners analyst Geoffrey Porges put it, confirming “our long held expectation that tezacaftor would prove to be both better, and better tolerated,” than lumacaftor—the med paired with ivacaftor in Orkambi.
Patients on the tezacaftor/ivacaftor regimen achieved an increase in FEV1, a measure of lung capacity, of more than 4%, while Orkambi’s label lists a benefit of more than 2.8%. And while the difference may not seem like a lot, it’s a much more significant one than analysts expected, with consensus pegging the FEV1 benefit at between 3.0% and 3.5%.
Combine that improvement with a lower rate of exacerbations, and “these data should compel more homozygous del508 patients to treatment, and are likely to bring patients back onto therapy who had discontinued Orkambi due to intolerability,” Porges wrote. And he’s expecting “rapid adoption” in the as-yet-untreated residual function patient group--who represent an opportunity of about $300 million—too.
Porges wasn’t the only analyst upbeat about the data. Jefferies’ Brian Abrahams called them “a win on all fronts" in his own note to clients, pointing out that the results also clear the way for “multiple shots on goal with ... triple combos” that the company has in the works.
“With two components now de-risked,” the company can move forward with any number of the potential trifectas it has in trials or in its preclinical pipeline, and “we believe this serves to further distance Vertex considerably from potential competitors.”
Vertex, for its part, will have to hope Porges and Abrahams are correct. It’s coming off a year in which an Orkambi sales slowdown prompted execs to drop projections for the med to between $950 million to $990 million from the $1 billion to $1.1 billion they had earlier forecast, and reimbursement roadblocks haven’t helped the combo’s cause, either. The 2017 guidance the Cambridge biotech rolled out in January hit below Street expectations, too, with Evercore ISI analysts pointing out at the time that the midpoint “appears ~17% lower than sell-side expectations.”