Phase 2, multicenter, OLE study to evaluate the long-term safety, tolerability, and efficacy of infigratinib, an FGFR (fibroblast growth factor receptor) 1-3-selective tyrosine kinase inhibitor, in participants with Hypochondroplasia (HCH) who previously completed ACCEL 2/3, and potentially additional participants who completed ACCEL. Participants rolling over directly from the observational ACCEL study must have had at least a 6-month period of growth assessment in that study.

Inclusion Criteria:

• Inclusion Criteria for Participants Rolling Over from ACCEL 2/3

  1. Pediatric participants with HCH who have completed ACCEL 2/3
  2. Negative pregnancy test in girls ≥10 years of age or girls of any age who have experienced menarche

Exclusion Criteria:

• Exclusion Criteria for Participants Rolling Over from ACCEL 2/3

  1. Participant has concurrent medical condition that, in the view of the PI and/or sponsor, would interfere with study participation or safety evaluations
  2. Participants who developed a medical condition that requires the initiation of treatment with a prohibited medication
  3. Participants who prematurely discontinued ACCEL 2/3
  4. Participants who have reached final height or near final height
  5. Current participation in an ongoing clinical study with a sponsor other than QED