Seven-year-old Josh Hardy of Fredericksburg, Virginia, is set to receive an experimental antiviral drug after his family’s appeal to its manufacturer, Chimerix, drew national attention and widespread public support. The company and the Food and Drug Administration agreed to expedite a clinical trial of brincidofovir, with Josh as its first patient.

Josh has survived several cancers since he was diagnosed with kidney cancer at nine months old. A recent bone marrow transplant left him without an effective immune system, and he developed an adenovirus infection in February. He remains in critical condition at St. Jude Children’s Research Hospital in Memphis, with heart and kidney failure.

Chimerix had initially declined the family’s request to provide the drug through “compassionate use,” a process that allows patients with serious illnesses to seek experimental medicines outside clinical trials. The company argued that doing so could slow development of the drug. St. Jude welcomed the agreement but cautioned that brincidofovir’s safety and effectiveness in children had not yet been established.

Under the new open-label study, the drug is expected to be available to 20 patients, beginning with Josh. Chimerix said the FDA had also committed to working with it on the design of a later Phase 3 study. Company president and CEO Kenneth Moch said he hoped the arrangement would help other patients in need as well.

Josh’s parents and supporters had pressed their case through television appearances, social media, petitions, phone calls and emails. A Facebook campaign attracted thousands of followers, and local organizations raised support for the family. Moch said the campaign also brought death threats against him and Chimerix employees.

After the announcement, Josh’s mother, Aimee, celebrated on Facebook, and his father, Todd, praised Moch’s efforts. The family’s supporters thanked “Josh’s Army” for helping bring attention to his case.