Efavirenz for the Treatment of Creutzfeldt-Jakob Disease

Inclusion Criteria: * Patients who meet the World Health Organization (WHO) diagnostic criteria for probable sporadic CJD or have a genetically confirmed diagnosis of hereditary CJD. * Age 18-80 years, any sex. * Baseline score on the Medical Research Council Prion Disease Rating Scale (MRC-PDRS) \>10 (i.e., retaining some functional ability). * The patient has a caregiver aged ≥18 years who can accompany the patient during the study and assist in providing relevant information. * The patient or their legally authorized representative has signed the informed consent form. Exclusion Criteria: * Presence of severe somatic diseases or unstable clinical conditions that may affect study compliance or patient safety, including malignancy, advanced liver or kidney dysfunction, severe cardiac disease (including patients with a history of significant QTc prolongation). * Current use of drugs that are known contraindications with efavirenz and cannot be discontinued or substituted. * Female participants who are pregnant or breastfeeding. * Other medical or psychiatric conditions, as judged by the investigator, that may interfere with the patient's participation in or completion of the study.