Amicus Therapeutics Expands Rare Disease Portfolio with $30M Deal for FSGS Drug

Amicus Therapeutics, a New Jersey-based orphan drug specialist, has made a significant move in the rare kidney disease space by acquiring U.S. rights to DMX-200, a late-phase drug candidate for focal segmental glomerulosclerosis (FSGS). The $30 million cash deal with Australian biotech Dimerix positions Amicus as a contender in a market currently dominated by Travere Therapeutics.

Strategic Acquisition Targets Unmet Medical Need

DMX-200, a CCR2 inhibitor, is currently in phase 3 trials for FSGS, a rare kidney disease with no FDA-approved therapies. Amicus' Chief Development Officer, Jeffrey Castelli, highlighted the drug's unique mechanism of action, which targets inflammatory signaling in damaged kidneys.

"DMX-200 is specifically targeting the inflammatory signaling in the damaged kidney," Castelli explained during a recent earnings call. This approach differs from other molecules that focus on hemodynamics, potentially offering a complementary treatment option for FSGS patients.

The deal structure includes up to $75 million in development and regulatory milestones, $35 million tied to the first sale, and potential sales milestones of up to $410 million. An additional $40 million is linked to future indications, underscoring Amicus' confidence in the drug's potential.

Differentiated Mechanism of Action

Amicus believes DMX-200's downstream blocking approach gives it an advantage over traditional binding inhibitors. Castelli elaborated on the drug's mechanism: "What happened with traditional binding inhibitors is MCP-1 couldn't dock. It actually led to a rebound effect where MCP-1 levels dramatically increase, which then would compete with the inhibitor and kind of lead to a muting effect."

In contrast, DMX-200 allows MCP-1 to dock and degrade, potentially maximizing its ability to suppress monocyte inflammation while preserving normal immune function outside the kidney.

Competitive Landscape and Market Potential

The FSGS market is heating up, with Travere Therapeutics filing for FDA approval of its drug Filspari in March. However, Amicus sees room for multiple approaches in treating this complex disease.

Castelli noted that patient response to different drugs may vary, stating, "Some patients will respond better to one drug than the other, and physicians will try to figure out which is the right approach for each individual."

As Dimerix's phase 3 trial progresses, with enrollment well underway and an upcoming interim analysis, Amicus is poised to challenge the current market landscape with a potentially differentiated treatment option for FSGS patients.