Shire scores new FDA thumbs-up for HAE drug Cinryze in latest bid to fend off rival CSL

Shire, which is in the process of being acquired by Takeda, is building its portfolio of drugs to treat hereditary angioedema. The FDA just approved a label extension of Cinryze. (FDA)

When CSL launched its hereditary angioedema drug Haegarda last year, it played up one big advantage the drug has over Shire’s Cinryze: Haegarda can be injected under the skin, while Cinryze is given twice a week by IV. Now Shire can boast a benefit its drug offers that CSL’s doesn’t: a new FDA approval for use in young children.

The FDA approved a label expansion for Cinryze that makes it available for preventing HAE attacks in children as young as 6. That could help Shire fend off an all-out attack from CSL, which has already stolen market share from its rival.

In the first quarter of this year, Shire announced that declining demand for Cinryze was partly to blame for flat sales in its HAE portfolio (PDF). The product had brought in $699 million in sales for Shire last year.

Both Cinryze and Haegarda are being marketed to fend off HAE attacks, which can cause spontaneous swelling of hands, feet and other areas of the body. In the most serious cases it can lead to life-threatening airway blockages.

People born with the disease experience their first attack at age 10, on average, according to Shire. With the label expansion, “children as young as 6 years old living with HAE now have the first FDA approved treatment option available to help prevent attacks,” said Andreas Busch, Ph.D., head of research and development of Shire, in a statement.

Just how much of a difference that advantage will make for Shire is unclear, given the ongoing and rather contentious competitive battle with CSL. Shire sued CSL to try to prevent the launch of Haegarda, arguing the new contender violated a patent on SHP616, Shire’s pipeline candidate, which can be administered subcutaneously. Shire is also waiting for an FDA verdict on lanadelumab (SHP643), another drug to prevent HAE attacks that can be administered under the skin.

But CSL was able to launch its product anyway last year—and it did so at an 18% discount to Cinryze.

"I think we were responsible in the way we priced [Haegarda] and making sure patients get it, and I think it will be the standard of care for some time to come," said CSL’s CEO Paul Perreault in an interview with FiercePharma in January.

RELATED: CSL chief says Haegarda launch timing, pricing were right on target

The HAE market battle is happening against the backdrop of Takeda’s proposed $62 billion acquisition of Shire. That deal is progressing, though not without some controversy of its own.

On May, a group of 12 Takeda shareholders demanded the deal be put up for a vote at the company’s shareholder meeting due to the “overly high risks” they felt the merger presented.

One major point of contention is that Takeda is financing 55% of the deal with newly issued shares, which critics say will cause too much dilution to current shareholders. The company may also take on significant debt, the opposition said.

RELATED: Takeda shareholders fear dilution, debt from Shire deal pose ‘high risks,’ demand shareholders vote on it

Since then, the group of dissenters has grown to 130, some of whom are former Takeda employees and members of the family who founded the Japanese company.

Still, 33% of shareholders would have to vote no on the deal for it to be derailed, and the dissenters are still a long way from reaching that threshold. Takeda plans to have a meeting for shareholders later this year or early next year to approve the new shares for funding the merger.