Shire's dominant position in the hereditary angioedema (HAE) market just firmed up with stellar data for its new candidate lanadelumab in the rare genetic disease class.
The drug candidate cut the rate of monthly attack in patients with HAE—a disease characterized by recurrent swelling of extremities, gastrointestinal tract and upper airways—by a whopping 87% compared to placebo in the phase 3 HELP trial, setting it on track for a filing in the U.S. later this year or in early 2018.
Shire picked up rights to kallikrein-blocking antibody when it bought Dyax for $5.9 billion two years ago. That deal that also brought in already marketed HAE treatment Kalbitor—bringing in a modest $52 million last year—to sit alongside its own and much larger Cinryze and Firazyr brands, which together made almost $1.3 billion.
Lanadelumab was seen as the big prize in the deal, however, with Shire predicting it could become a $2 billion drug at peak thanks to a favorable dosing regimen of a subcutaneous injection every two or four weeks.
The new data suggested that despite the sizable price tag for Dyax, the deal could pay off for Shire. In the HELP study, all three of the doses tested achieved a significant reduction in HAE attacks, with a 300mg dose given every other week giving the best result. Shire's CEO Flemming Ornskov said the study showed that lanadelumab has "high potential for transforming the way patients living with this condition are treated."
In the U.S. at the moment, prophylaxis against HAE requires an intravenous infusion given twice a week, or injections to tackle acute attacks, according to Aleena Banerji, M.D., one of the investigators who works in Massachusetts General Hospital.
"If approved, lanadelumab may offer patients a long-acting treatment option that significantly reduces HAE attacks when administered subcutaneously as infrequently as every four weeks," she said.
Approval of lanadelumab would help Shire weather the patent expiry on Firazyr—used to treat acute HAE attacks—which is due next year and will put almost $600 million in sales at risk of generic erosion.
Cinryze too is starting to come under pressure from new entrants into the HAE prevention category, notably CSL Behring's promising C1 esterase inhibitor Haegerda. The drug can be given by subcutaneous injection rather than infusion and was filed for approval in the U.S. last August. Shire—which is also developing a subcutaneously administered follow-up to Cinryze—recently launched a lawsuit claiming CSL's drug infringes on its patents.