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Study on the Use of Romosozumab and Zoledronic Acid for Treating Osteoporosis in Patients

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What is this trial about?

A plain-language summary of the goals, design and what participants do

The OPTIMIST study is focused on understanding the best way to use romosozumab for treating osteoporosis. Osteoporosis is a condition where bones become weak and are more likely to break. The study will explore three different treatment strategies to find the most effective approach. Romosozumab is a medication given as a solution for injection, and it works by helping to strengthen bones.

Participants in the study will receive either romosozumab or a placebo, which is a substance with no active medication. Another medication, zoledronic acid, may also be used in the study. Zoledronic acid is given as a solution for infusion, which means it is administered directly into the bloodstream through a vein. The study aims to see how these treatments affect bone density and other aspects of bone health over time.

The study will last for up to 52 weeks, during which participants will receive regular treatments and have their bone health monitored. The goal is to determine how these treatments can best be used to improve bone strength and reduce the risk of fractures in people with osteoporosis. The findings from this study could help improve treatment options for those living with this condition.

The research process

The trial runs in 5 steps – from screening to follow-up. Each step says what happens and what the team monitors.

  1. Step 1

    Enrollment and initial assessment

    Upon joining the study, you will undergo an initial assessment to confirm eligibility. This includes checking if you are a postmenopausal woman with osteoporosis, defined by a bone density test showing a T-score less than -2.5, or if you have had an osteoporotic fracture in specific areas within the last three years after age 50.

  2. Step 2

    Treatment phase 1

    You will receive romosozumab through a subcutaneous injection once a month. The dosage is 105 mg, administered using a pre-filled syringe. This phase will last for a specified duration as part of the study's treatment strategy.

  3. Step 3

    Treatment phase 2

    Following the initial treatment phase, you may receive zoledronic acid through an intravenous administration. The dosage is 5 mg, provided as a solution for infusion. The frequency and duration will be determined based on the study's protocol.

  4. Step 4

    Monitoring and assessments

    Throughout the trial, regular monitoring will occur to assess changes in bone density at the hip, spine, and femoral neck over 24 months. Additional assessments will include bone microarchitecture, bone turnover markers, and bone biopsies to evaluate bone health and response to treatment.

  5. Step 5

    Final evaluation

    At the end of the trial, a final evaluation will be conducted to measure the overall changes in bone density and other health markers. This will help determine the effectiveness of the treatment strategies used in the study.

Who can join the trial?

3 criteria

  • Must be a postmenopausal woman. This means a woman who has stopped having menstrual periods.
  • Must have osteoporosis, which is a condition where bones become weak and are more likely to break. This is defined by a bone density test showing a BMD T-score of less than -2.5 at the spine, total hip, or femoral neck. A BMD T-score is a measurement that compares your bone density to a healthy young adult's bone density.
  • Must have had an osteoporotic fracture in the spine, hip, pelvis, forearm, or upper arm (humerus) within the last 3 years after turning 50 years old. An osteoporotic fracture is a break in a bone that happens more easily because the bones are weaker.

Who cannot join the trial?

3 criteria

  • Patients who are male cannot participate. This study is only for females.
  • Patients who are not within the specified age range cannot participate. The study is for certain age groups only.
  • Patients who are part of a vulnerable population cannot participate. This means people who might need special protection or care.
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Investigated drugs

Romosozumab is a medication used in the treatment of osteoporosis, a condition that weakens bones and makes them more likely to break. This medication works by helping to build new bone and increase bone strength. It is typically given as an injection and is used to reduce the risk of fractures in people with osteoporosis. In this clinical trial, the goal is to find the best way to use romosozumab to treat osteoporosis by testing different treatment strategies.

What is already known about the treatment

Romosozumab – Romosozumab is administered as an injection under the skin, typically in the upper arm, thigh, or abdomen. It is currently being studied in clinical trials to determine the best way to use it for treating osteoporosis, a condition that weakens bones and makes them more likely to break. Romosozumab works by blocking a protein in the body that slows down bone formation, which helps to increase bone density and strength. It is classified as a bone-building medication, specifically a monoclonal antibody, which means it is designed to target specific proteins in the body to achieve its effects.

Investigated diseases

Osteoporosis – Osteoporosis is a condition characterized by weakened bones, which increases the risk of fractures. It occurs when the creation of new bone doesn't keep up with the removal of old bone. As the disease progresses, bones become more porous and fragile, often without any symptoms until a fracture occurs. Common fracture sites include the hip, spine, and wrist. The disease can lead to a decrease in height over time and a stooped posture. Bone density tests are often used to measure the progression of bone loss.
Trial detailsLast updated 2 Oct 2026
Age18+ yearsPhasePhase ITrial ID2023-505940-20-00Estimated enrolment270 patientsSponsorRegion Midtjylland

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On this site, “treatment” means an investigational medicine being studied in a clinical trial. Its safety and efficacy for the use being studied have not yet been confirmed, some participants may receive a placebo or a comparator medicine, and taking part does not guarantee any health benefit. The decision to take part is made by the doctor at the research site. This site is for information only and does not replace medical advice.

This service is not affiliated with the European Commission, the EMA, or the official CTIS system. Most information comes from publicly available international clinical-trial registries, supplemented by data from academic sites, national regulators and commercial sponsors. On this site, “treatment” and “therapy” mean a medicine being tested in a clinical trial. Its safety and effectiveness in the use being studied are not yet confirmed, some participants may receive a placebo or a comparator, and taking part does not guarantee a health benefit. The doctor at the research site decides who can take part. This site provides information, not medical advice. Certain content and visual elements on this website have been generated or enhanced using artificial intelligence (AI).