Rare disease drug developer BioMarin Pharmaceutical is buying its way to revenue growth with a $4.8 billion deal for Amicus Therapeutics, a company whose two commercialized products each offer blockbuster potential and also complement their acquirer’s long history in rare enzyme deficiency therapies.
The deal announced Friday is the second acquisition for BioMarin under CEO Alexander Hardy, the Genentech veteran who joined the company two years ago. At that time, BioMarin envisioned new growth would come from the hemophilia A gene therapy, Roctavian. But lackluster sales of the product have led the company to pivot, turning to M&A to build out its pipeline and portfolio.
BioMarin’s first commercialized product was an enzyme replacement therapy and the San Rafael, California-based biotech currently markets five such products. The portfolio is led by a newer product, Voxzogo, a treatment for achondroplasia, the most common form of dwarfism. Approved in 2021, this peptide drug has become BioMarin’s top seller. But looming competition in this indication from Ascendis Pharma and BridgeBio Pharma is putting pressure on BioMarin to find other ways to grow revenue.
“We’re doing this [acquisition], as we said, with regard to [business development], because we have a compelling set of capabilities and we have the abilities to do deals and create value for our shareholders,” Hardy said during a Friday morning conference call. “At the same time, we’re very confident of our ability to compete with Voxzogo in achondroplasia. But we can do many things at the same time and we can create extraordinary value, we believe, for all of our stakeholders by doing deals such as this one.”
For the nine months ended Sept. 30, BioMarin reported $2.3 billion in revenue. Roctavian accounted for just $23 million of that total. In October, BioMarin announced it would pursue options to divest the gene therapy. The Amicus acquisition continues BioMarin’s strategy of embracing its strengths in rare enzyme deficiencies. In May, it agreed to pay $270 million to acquire Inozyme Pharma, whose lead program is in late-stage development for an enzyme deficiency that currently has no FDA-approved therapies. When that deal was announced, Hardy said the Inozyme therapy will benefit from BioMarin’s experience identifying eligible patients to grow sales for its enzyme deficiency therapies. On Friday, he said the same thing about the Amicus products.
Amicus was founded in 2005 by John Crowley, an entrepreneur who was pursuing new treatments for two of his children born with the rare enzyme deficiency Pompe disease. The biotech’s first commercialized product was Galafold, a drug approved in 2018 for a different enzyme deficiency named Fabry disease. In 2023, Amicus won FDA approval for Pombiliti and Opfolda, a two-drug regimen for Pompe. Combined, these Amicus products accounted for $448.9 million in revenue in the first nine months of 2025, an 18.5% increase compared to the same period in 2024.
BioMarin Chief Financial Officer Brian Mueller said that despite the size of the acquisition, the deal does not come with any clinical trial risk and the two commercialized Amicus products bring a base of revenue that is growing at a faster rate than BioMarin’s portfolio. The company projects each Amicus product will become a blockbuster seller. Hardy added that the cash flow from the business combination will enable BioMarin to build up its financial reserves within the next 12 to 24 months to deploy toward more deals. In the meantime, he said BioMarin will explore smaller deals to build out its R&D pipeline.
The Amicus acquisition is expected to immediately accelerate BioMarin’s revenue growth, Leerink Partners analyst Joseph Schwartz said in a note sent to investors. The firm estimates the two commercialized Amicus products will tally $630 million in 2025 revenue, growing to more than $1 billion by 2027 and nearly $2 billion by 2035. Schwartz added that while there are few details on synergies and cost savings, in general the business combination “looks very logical based on the strategic and financial overlap.”
“We have long heard from the company regarding their durable and growing enzyme therapy business, so the acquisition of Amicus makes perfect sense to us,” he said.
The acquisition terms announced Friday call for BioMarin to pay $14.50 in cash for each Amicus share, which is a 33% premium to Thursday’s closing price and a 58% premium to the stock’s average price for the past 60 days. BioMarin said it plans to finance the transaction with cash on hand and about $3.7 billion in debt financing. The boards of directors of both companies have approved the deal, which still needs the approval of Amicus shareholders and regulators. The companies expect to complete the transaction in the second quarter of 2026.
Photo illustration: Piotr Swat/SOPA Images/LightRocket, via Getty Images

