Amicus Therapeutics (NASDAQ: FOLD) is focused on rare and orphan diseases. So it’s no head-scratcher that the Cranbury, New Jersey-based biotech agreed to shell out $100 million to acquire Celenex. a clinical-stage gene therapy company in Columbus, Ohio.

Celenex’ lead programs in CLN6, CLN3 and CLN8 Batten disease are potential first-to-market curative therapies for these rare, devestating diseases. Batten disease, also known as Neuronal Ceroid Lipofuscinosis (NCL), is a family of rare disorders that can be life-threatening and debilitating, with high unmet need.

With this acquisition, Amicus gains the worldwide development and commercial rights for 10 gene therapy programs developed at The Center for Gene Therapy at The Research Institute at Nationwide Children’s Hospital and The Ohio State University.

In addition to the $100 million in cash, Celenex shareholders are also eligible for up to $15 million in development milestones and $262 million in BLA/MAA submission and approval milestones across multiple programs.

Amicus expects to pay no more than $75 million over the next 4 years in these milestones. No royalties are owed to Celenex for any of these programs.  Celenex shareholders may also be eligible for up to $75 million in tiered sales ($500 million/$750 million) milestone payments.