Seven-year-old Josh Hardy, a first-grader from Fredericksburg, Virginia, will receive an experimental antiviral drug after his family’s campaign drew national attention to his critical condition. Chimerix, the drug’s manufacturer, worked with the U.S. Food and Drug Administration to make him the first patient in a new clinical trial of brincidofovir.

Josh has battled cancer since he was diagnosed with kidney cancer at nine months old. After cancers also appeared in his thymus, lung and bone marrow, he underwent a bone marrow transplant that left him without a functioning immune system. He subsequently developed an adenovirus infection and was in intensive care at St. Jude Children’s Research Hospital in Memphis, experiencing heart and kidney failure.

Chimerix had initially declined the family’s request for the unapproved drug, saying that providing it outside a trial could slow its development. Federal policy permits companies to provide experimental medicines to seriously ill patients through “compassionate use,” but companies can decline requests. Chimerix CEO Kenneth Moch said the company had received more than 80 such requests for brincidofovir over the previous two years.

The family and its supporters pressed their case through television appearances, social media, petitions, phone calls and emails. A Facebook support page attracted about 15,000 followers, while local businesses and charities also rallied around the family. Moch said the campaign brought support but also death threats against him and company employees.

Under the agreement with the FDA, Josh was expected to receive the drug on Wednesday as the first of 20 patients in an open-label study. The FDA also committed to work with Chimerix on the design of a later Phase 3 study. Josh’s parents welcomed the decision and thanked the company and supporters. St. Jude said his condition remained critical and complex, and cautioned that the drug’s safety and effectiveness in children had not yet been established.