This is a Phase 2 study of SPR001 for the treatment of classic CAH that will provide 12 weeks of open-label treatment to eligible subjects.

This is a Phase 2 study of SPR001 for the treatment of classic CAH that will provide 12 weeks of open-label treatment to eligible subjects. To be eligible for this study, an individual must either have completed Study SPR001-201 or meet eligibility criteria for SPR001-naïve subjects. The expected duration of study participation for each subject is up to approximately 5 months. This includes a screening period of ≤30 days, a treatment period of 12 weeks, and a safety follow-up period of 30 days.

Inclusion Criteria:

• Is approved by the Sponsor's Medical Monitor
• Is on a stable regimen of glucocorticoid replacement for ≥30 days before baseline that is expected to remain stable throughout the study
• If screening for this study occurs >3 months after the subject's final follow-up visit in Study SPR001-201, the subject will have serum 17-OHP measured at screening.
• Agrees to follow contraception guidelines
• Is able to understand all study procedures and risks involved and provides written informed consent indicating willingness to comply with all aspects of the protocol

Exclusion Criteria:

• Experienced a clinically significant AE considered at least possibly related to SPR001 in Study SPR001-201
• If screening for this study occurs >3 months after the subject's final follow-up visit in Study SPR001-201, the subject will be screened for any clinically significant unstable medical condition, medically significant illness, or chronic disease occurring within 30 days of screening
• Is at increased risk of suicide
• Clinically significant depression or anxiety at screening or baseline
• Clinically significant abnormal clinical or laboratory assessments must be discussed with the Medical Monitor to determine eligibility for this study.
• Subjects who routinely work overnight shifts require Medical Monitor approval for enrollment
• Females who are pregnant or lactating
• Use of any other investigational drug within 30 days or 5 half-lives before screening
• Use of prohibited concomitant medications (including rosiglitazone, testosterone, and strong inhibitors and/or inducers of CYP3A4) within 30 days or 5 half-lives of baseline. Medications metabolized by CYP3A4, 2C8, 2C9, or 2C19, especially those that are sensitive substrates or substrates with narrow therapeutic ranges should be discussed on a case-by-case basis with the Medical Monitor.