BioMarin Bet on Amicus To Ease Voxzogo’s Decline

 

The rare disease drugmaker is facing potential competitors for achondroplasia drug Voxzogo. Is a big M&A deal with two approved assets enough to maintain investor interest?

BioMarin made a splash just before the holidays with the $4.9 billion purchase of rare disease biotech Amicus Therapeutics. With that buy, BioMarin tried to stuff its own stocking with a solution to the decline of one of its biggest money-makers, achondroplasia drug Voxzogo, which accounted for more than one-quarter of the company’s revenue in 2024.

But a number of different companies are competing in the billion-dollar-plus achondroplasia market, aiming to beat BioMarin with easier dosing and higher efficacy than Voxzogo. In the face of such competition, BioMarin is betting on Amicus’ two approved therapies, also in the rare disease space, to step in to fill what will likely be a growing revenue void. The move comes in the midst of a long, steady decline of the company’s shares—down almost 9% over the last year and 30% over the last five.

While BioMarin is not operating on a one-product revenue base, shares of the company do “trade on Voxzogo, mostly, not on earnings beats,” Mitchell Kapoor, a senior analyst at HC Wainwright, told BioSpace.

Amicus Brief

In September 2024, BioMarin declared a $4 billion annual revenue goal. A year later it abandoned that hope, in part citing competitive headwinds facing Voxzogo, which earned $735 million in 2024. In particular, Ascendis Pharma and BridgeBio are each developing their own achondroplasia drugs.

To fight off the bites those companies would take into BioMarin’s bottom line, BioMarin moved to buy Amicus, “which brings two commercial assets of note,” Kapoor said. Those two assets are Galafold, an oral treatment for Fabry disease, and Pombiliti/Opfolda, a combination therapy for Pompe disease. According to the announcement of the Amicus deal, those two drugs together brought in $599 million in the four quarters preceding the deal.

In its 2024 earnings report, Amicus projected that sales of those two drugs could grow up to $1 billion each in the 2030s. Whether that’s enough to avoid an overall dip in revenue for BioMarin remains to be seen. Wall Street expects Voxzogo sales to remain consistent into next decade, but Kapoor predicts sales of the drug will “probably stall quite soon.”

BioMarin declined to comment for this story, but pointed BioSpace to its presentation at the 2026 J.P. Morgan Healthcare Conference in January. CEO Alexander Hardy said that Galafold and Pombiliti/Opfolda “just drop perfectly into our enzyme therapy business,” again citing Amicus’ $1 billion prediction for the two drugs.

“Adding Amicus further strengthens that growth outlook and [diversifies] our revenue base,” Hardy added.

Further down the line, BioMarin has a next-generation achondroplasia drug, called BMN333. But with only Phase 1 data in hand so far, that therapy remains a “prove-it story,” according to Kapoor.

Those early data do suggest BMN333 may offer a step up in efficacy from Voxzogo, he added, but it’s unclear if that will be enough to keep investors interested in BioMarin. BMN333 is an injectable like Voxzogo, Kapoor continued, while others such as BridgeBio are developing oral drugs with the goal of higher efficacy.

“In terms of a growth engine where investors can get excited, I don’t think that this is necessarily the story that people can really get behind as a next-generation wave of therapies that they’re going to wow the Street with.”

Stiff Competition

Voxzogo was first approved in 2021. The drug addresses achondroplasia, a genetic disorder and the most common cause of dwarfism, affecting 250,000 people worldwide. The FDA greenlight came after Voxzogo stimulated bone growth in a Phase 3 trial as compared to placebo. This marked the first time a drug improved growth in children with the condition.

But in the four years since achieving FDA approval, other companies have begun to show superior efficacy and dosing in the clinic.

BridgeBio is developing infigratinib, a rival, oral treatment for achondroplasia. In June 2024, the company announced Phase 2 data showing that children taking the drug had grown at an average annualized rate of 2.51 cm after 12 months of treatment, and 2.50 cm at 18 months.

“It’s a big deal,” Kapoor said, “not to mention that efficacy is on par” with Voxzogo.

Even closer to the clinic is Ascendis Pharma’s TransCon CNP, which awaits an FDA approval decision by February 28. In September 2024, the company announced that children taking TransCon CNP achieved 5.89 cm/year in growth compared to 4.41 cm/year in children taking placebo. The drug received Priority Review from the FDA. While it’s still injectable, TransCon CNP is only once-per-week, versus Voxzogo’s once-per-day administration.

“That drug is very similar [to Voxzogo], and more convenient,” Kapoor said.

There’s also Tyra Biosciences, which is “more of a longshot,” according to Kapoor. Tyra’s oral drug dabogratinib has the potential to be more effective than Voxzogo, but is another “prove-it story,” Kapoor said. Phase 2 trials just started this past August. Dabogratinib could potentially be the first therapy that treats the underlying cause of achondroplasia—mutations in the FGFR3 gene—William Blair analysts wrote on Feb. 10. The analysts added that if patients in the Phase 2 trial achieve 7 cm or more of annualized growth in six months, “dabogratinib could be on track to set a new therapeutic standard in ACH.”

As these competitors seek to unseat one of BioMarin’s biggest earners, the company is trying to set up its next act. “[BioMarin has] acknowledged there are headwinds,” Kapoor said. “Then it’s like, What’s next?”

https://www.biospace.com/business/biomarin-bet-on-amicus-to-ease-voxzogos-decline-will-it-work