A Phase 2 interventional study of Alendronate Sodium in Sickle Cell Disease, Sickle Cell Anemia and Osteonecrosis, sponsored by University of California, Davis. Recruiting at 1 site in United States. Open to participants aged 18 Years to 80 Years. Per ClinicalTrials.gov, last updated 2026-07-16.
Sponsored by University of California, Davis · Phase 2, Interventional, and Treatment
A prospective, single-arm, intervention study of oral alendronate in adults with sickle cell disease and osteonecrosis
The investigators hypothesize that adults with sickle cell disease (SCD) and osteonecrosis of the femoral (hip) and/or humeral (shoulder) heads will tolerate oral alendronate 70 mg administered once a week x 24 weeks (6 months). In addition to collecting safety and tolerability data on alendronate in study participants, the investigators will also measure the preliminary efficacy of alendronate using changes in the Adult Sickle Cell Quality of Life Measurement System (ASCQ-Me) Pain Impact scores from baseline to 3-months and 6-months after alendronate initiation. Serum and urine specimen will also be collected to assess changes in bone biomarkers at baseline, 3-months, and 6-months.
The investigators plan to recruit 24 adults with SCD from the University of California Davis Medical Center to this single-arm, open label, interventional study. The investigators anticipate enrolling 1-2 participants per month between Sep 2024- Dec 2025.
The study endpoints are summarized below:
The investigators' goal is to complete primary data analysis by May 2026.
1,134 studies on the registry are indexed under Anemia, Sickle Cell; 238 are open to participants now.
This study's planned enrollment of 30 is below the median of 40 across 769 interventional studies indexed under Anemia, Sickle Cell.
Browse Anemia, Sickle Cell studies →University of California, Davis is the lead sponsor of 809 studies on the registry; 142 are open to participants now.
Of its 67 completed or terminated interventional studies of FDA-regulated products, 43 (64%) have results posted.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
The protein in red blood cells that carries oxygen. A low level is anaemia, which can cause tiredness and breathlessness. Measured in g/dL or g/L (9 g/dL is 90 g/L).
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).
Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.
Hemoglobin (Hb)
The protein in red blood cells that carries oxygen. A low level is anaemia, which can cause tiredness and breathlessness. Measured in g/dL or g/L (9 g/dL is 90 g/L).
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Childbearing potential
Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).
Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Single-arm prospective cohort of 30 adult with SCD
Drug: Alendronate Sodium
Administer oral alendronate 70 mg once a week x 24 weeks to all study participants
Also known as: alendronate tablet, oral alendronate, Fosamax, Binosto
Recruitment and retention rates
Proportion of eligible patients who get recruited to the study; number of enrolled patients who complete 6-month study
Time frame: up to 28 weeks
Incidence of Treatment-Emergent Adverse Events as assessed by participant report
Collect all adverse events reported by patients and determine if related to study drug
Time frame: up to 28 weeks
Pain assessed by the Adult Sickle Cell Quality of Life Measurement System (ASCQ-Me) Pain Impact questionnaire
The Adult Sickle Cell Quality of Life Measurement System (ASCQ-Me) Pain Impact questionnaire is a patient-reported outcome measure of pain level in the past 7 days. The ASCQ-Me pain scale ranges from 0-100, with a standardized mean of 50 and a standard deviation of 10, where lower scores signify worse disease impact.
Time frame: up to 28 weeks
Bone turnover markers
Measure longitudinal changes in of biomarkers for osteoclast (bone resorption) and osteoblast (bone formation) activity
Time frame: Baseline, then every 2 months until end of study
Inflammatory biomarkers
Measure longitudinal changes in inflammatory biomarkers from baseline to the end of the study
Time frame: Baseline, then every 2 months until the end of the study
Vascular adhesion biomarkers
Measure longitudinal changes in biomarkers of vascular adhesion from baseline until the end of the study
Time frame: Baseline, then every 2 months until the end of the study
Plan to share: No
No publications or documents are linked to this record.
Started Mar 2026 (actual). Primary completion is estimated for Sep 2027, 18 months after the start.
Of 58 non-industry phase 2 interventional studies under Anemia, Sickle Cell, half reached primary completion within 54 months of starting (the median), counting those still running; a quarter within 42 and three quarters within 117. This study's planned 18 months is below that.
Counting every sponsor, half of 92 studies reached it within 46 months; a quarter within 24 and three quarters within 73.
How these figures are worked out, and which studies are left out of them.
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Studies of the drug tested here: Alendronate
University of California, Davis →