Low Dose Danazol for the Treatment of Telomere Related Diseases
Background: DNA is a structure in the body. It contains data about how the body develops and works. Telomeres are found on the end of chromosomes in DNA. Some people with short telomeres or other gene changes can develop diseases of the bone marrow, lung, and liver. Researchers want to see if low doses of the hormone drug danazol can help.
Objective: To study the safety and effect of low dose danazol.
Eligibility: People ages 3 and older with a telomere disease who have either very short telomeres and a specific gene change. They must also show signs of aplastic anemia, lung, or liver disease.
Design: Participants will be screened in another protocol. Participants will have: * Medical history * Physical exam * Blood tests * Lung exam. They will breathe into an instrument that records the amount and rate of air breathed in and out over a period of time. 6-minute walking test. * Abdominal ultrasound and liver scan. These tests use sound waves to measure the fibrosis in the liver. Some participants will have: * Pregnancy test * Small sample of the liver removed * Bone marrow biopsy. The bone will be numbed and a small needle will take a sample of the marrow. All participants will have hormone levels checked. All child participants will see a pediatric endocrinologist. Children may need to have a hand x-ray. We will monitor patients for 6 months before starting danazol. Participants will take danazol by mouth twice a day for 1 year. Participants must return to the clinic at 6 months and 12 months while on danazol and 6 months after stopping it. They will have blood and urine tests, a lung exam, abdominal ultrasound, and liver scan.
⁃ Age-adjusted telomere length less than or equal to the first percentile by flow-FISH method. In patients with a known pathogenic or likely pathogenic mutation in a telomere maintenance gene, age adjusted telomere length less than or equal to the 10th percentile is sufficient.
• A mutation in telomere maintenance genes (TERT, TERC, DKC1, TINF2, NHP2, NOP10, WRAP53, TERF2, PARN, RTEL1, ACD, CTC1, USB1) as tested in a CLIA (or international equivalent) certified laboratory
• Age greater than or equal to 3 years
• Weight greater than or equal to 12 Kg
⁃ AND
• At least one of the following criteria:
∙ Anemia with a hemoglobin less than or equal to 10 g/dL without red blood cell transfusion
‣ Thrombocytopenia with a platelet count less than or equal to 50,000/microliter without transfusion
‣ Neutropenia with an absolute neutrophil count less than or equal to 1,000/ microliter
⁃ OR
⁃ Pulmonary fibrosis diagnosed by either a lung biopsy or computed tomography scan of the chest according to guidelines from the American Thoracic Society and European Respiratory Society.
⁃ OR
• Hepatic fibrosis diagnosed by Transient Elastography by Fibroscan value greater than 10 kpa or US evidence of cirrhotic liver or splenomegaly, or transjugular liver biopsy demonstrating fibrosis.