Yes, Evenity (romosozumab) significantly increases bone-specific alkaline phosphatase
Romosozumab produces a marked early increase in bone formation markers, including bone-specific alkaline phosphatase, as part of its dual mechanism of action that both stimulates bone formation and reduces bone resorption. 1
Mechanism and Bone Turnover Marker Response
Romosozumab works by blocking sclerostin binding to osteoblasts, which allows osteoblast activity to increase substantially. The 2020 AACE/ACE guidelines explicitly state that "BTMs suggest an early anabolic effect" with romosozumab treatment 1. This translates to:
- Significant increases in bone formation markers (including bone-specific alkaline phosphatase and P1NP) occur early in treatment, typically peaking around month 3
- These increases indicate good pharmacologic response to the anabolic therapy 2
- The elevation in bone formation markers is accompanied by simultaneous decreases in bone resorption markers
Clinical Evidence
The guidelines recommend using bone turnover markers to assess patient compliance and treatment efficacy, noting that "significant increases indicate good response to anabolic therapy" 2. In real-world studies, bone alkaline phosphatase increased substantially at 6 months with romosozumab treatment 3.
Important Clinical Context
One notable exception exists: In patients with hypophosphatasia (a rare genetic condition with inherently low alkaline phosphatase), romosozumab did not significantly impact serum alkaline phosphatase levels, yet still improved bone mineral density substantially 4. This represents a unique scenario where the typical bone formation marker response is blunted due to the underlying genetic defect.
Monitoring Implications
The AACE guidelines recommend considering bone turnover markers for:
- Assessment of patient compliance
- Verification of pharmacologic response
- Significant increases in bone formation markers serve as confirmation of appropriate anabolic response 2
The early anabolic effect demonstrated by rising bone-specific alkaline phosphatase correlates with the dramatic increases in bone density and improvements in bone microarchitecture seen with romosozumab treatment 1.