Strontium Ranelate and Fracture Risk: Clinical Evidence
Yes, multiple high-quality randomized controlled trials demonstrate that strontium ranelate significantly reduces both vertebral and non-vertebral fracture risk in postmenopausal women with osteoporosis, with sustained efficacy over 10 years of treatment.
Evidence for Fracture Risk Reduction
Vertebral Fractures
- Strontium ranelate reduces vertebral fracture risk by 41% over 3 years and 49% in the first year of treatment in postmenopausal women with established osteoporosis 1
- The anti-fracture efficacy is sustained long-term, with a 35% relative risk reduction maintained between years 6-10 of continuous treatment 2
- In women ≥80 years old specifically, vertebral fracture risk decreased by 32% over 3 years and 31% over 5 years 3, 4
Non-Vertebral Fractures
- Non-vertebral fracture risk is reduced by 15% over 5 years in the general osteoporotic population 5
- In elderly women ≥80 years, non-vertebral fracture risk decreased by 31% over 3 years and 27% over 5 years 3, 4
- Major non-vertebral fractures were reduced by 33% in women over 80 4
- The 10-year data show a 38% relative risk reduction for non-vertebral fractures compared to matched placebo controls 2
Hip Fractures
- In high-risk patients (age ≥74 years with low BMD), hip fracture risk was reduced by 43% over 5 years 5
- Women over 80 years experienced a 24% hip fracture risk reduction (though not statistically significant in this subgroup alone) 4
Key Study Populations and Design
The evidence comes primarily from two landmark trials:
- SOTI (Spinal Osteoporosis Therapeutic Intervention) and TROPOS (Treatment of Peripheral Osteoporosis): Combined enrollment of 5,091 postmenopausal women with osteoporosis, followed for 5 years in double-blind, placebo-controlled design 5
- Open-label extensions followed 237 patients for up to 10 years, demonstrating sustained efficacy 2
- Elderly subgroup analyses specifically evaluated 1,488-1,489 women aged 80-100 years 3, 4
Efficacy Across Risk Levels
A meta-analysis of SOTI and TROPOS data found that strontium ranelate's efficacy does not vary significantly with baseline fracture probability as assessed by FRAX® 6. This means the drug works effectively across the spectrum of fracture risk, from moderate to very high risk patients.
Bone Mineral Density Effects
- Lumbar spine BMD increased by 14.4% at 3 years and continued to rise to 34.5% at 10 years 1, 2
- Femoral neck BMD increased by 8.3% at 3 years 1
- These BMD gains are sustained and progressive throughout long-term treatment 7, 8
Safety Profile
The long-term safety data through 10 years shows strontium ranelate was well-tolerated with a safety profile similar to placebo 2, 5. The medication maintains normal bone mineralization quality without adverse changes at the crystal level 8.
Important Context: Current Clinical Status
Critical caveat: While the evidence for strontium ranelate's anti-fracture efficacy is robust, this medication has been withdrawn or severely restricted in many countries due to cardiovascular and venous thromboembolism concerns identified in post-marketing surveillance. The 2023 American College of Physicians guidelines 9 and 2024 evidence-based guidelines 10 do not include strontium ranelate in their treatment recommendations, focusing instead on bisphosphonates, denosumab, and anabolic agents.
Clinical Bottom Line
The research evidence unequivocally demonstrates strontium ranelate's efficacy in reducing fractures across all age groups and fracture types in postmenopausal osteoporosis. However, current clinical practice has moved away from this agent in favor of bisphosphonates as first-line therapy 9, denosumab as second-line 9, and anabolic agents for very high-risk patients 10, based on more favorable benefit-risk profiles and contemporary safety data.