Sangamo Therapeutics Inc and Pfizer Inc said on Wednesday they would work together to develop a gene therapy to treat ALS, a disease that affects nerve cells in the brain and the spinal cord.

The gene therapy will also be used to treat patients with a brain disorder caused by mutations of a gene that is linked to about a third of hereditary ALS cases.

The partnership comes at a time when gene therapy is gaining momentum, after several high profile failures in the late 1990s and early 2000s, with the U.S. Food and Drug Administration recently updating guidance to help speed up development of such treatments.

The agency last month approved Spark Therapeutics Inc’s treatment for a rare form of blindness, marking the first approval of a gene therapy for an inherited disease.

Under the terms of the deal, Sangamo will receive a $12 million upfront payment from Pfizer and an additional $150 million in milestone payments, the companies said.

ALS (amyotrophic lateral sclerosis), whose sufferers include renowned British physicist Stephen Hawking, attracted international attention in 2014 with the “Ice Bucket Challenge”, in which people posted videos of pouring ice-cold water on themselves to encourage donations to research.

Shares of Sangamo were up 5.4 percent at $18.50, while those of Pfizer were up marginally before the bell on Wednesday.