TA906 · STA
Rimegepant is recommended for preventing episodic migraine in adults who have at least 4 and fewer than 15 migraine attacks per month, if at least 3 preventative treatments have not worked. Treatment should be stopped after 12 weeks if the frequency of migraine attacks does not reduce by at least 50%. Where more than 1 treatment is suitable, the least expensive option should be chosen.
Source documents
Intervention
Conditions
Comparators
| Name | Type | Established | Committee preferred |
|---|---|---|---|
| erenumab | active drug | Yes | — |
| fremanezumab | active drug | Yes | — |
| galcanezumab | active drug | Yes | — |
Clinical trials
| Trial | Design | Phase | Pivotal |
|---|---|---|---|
| BHV3000-305 | RCT | 2/3 | Yes |
Economic model
ICER
Methodological decisions (8)
Healthcare resource use costs perspective: primary care vs secondary care. Company used primary care approach; ERG used secondary care approach
Company: Primary care approach reflecting potential for GP prescribing with one-off starting cost and 3-month follow-up cost plus neurologist referral cost for comparators
ERG: Secondary care approach. Not convinced by main rimegepant costs in primary care given committee's conclusions that specialist involvement needed. Clinical advice suggested neurologist follow-up more likely 6-monthly then yearly
Committee: Specialist costs in secondary care should be included alongside primary care costs. Rimegepant would most likely be started by a specialist due to its position in treatment pathway, possibly via shared care agreement for ongoing GP prescribing
ICER impact: increases
Company initially used BHV3000-305 trial outcome definition (50% reduction in moderate-to-severe MMDs in last 4 weeks); ERG preferred NMA definition (50% reduction in any severity MMDs as average over 12 weeks) for consistency across comparisons
Company: Response assessment at 12 weeks using trial definition from BHV3000-305 (moderate-to-severe MMDs, last 4 weeks)
ERG: Response should be defined as average over 12 weeks using any severity MMDs, consistent with NMA definition
Committee: Average over 12 weeks to ensure consistency across model inputs
ICER impact: uncertain_direction
Trial evidence excluded treatment-experienced patients but company proposed use after 3 failed treatments
Company: Evidence from comparator trials suggests rimegepant results may be conservative in refractory population
ERG: Evidence is uncertain and does not show substantial difference between refractory and non-refractory migraine
Committee: Clinical evidence from NMA not aligned with company positioning; took uncertainty into account in decision making
ICER impact: uncertain_direction
Definition of response: proportion with ≥50% reduction in mean monthly migraine days compared with baseline. Company initially proposed endpoint at 12 weeks in last 4 weeks; ERG and committee preferred 12-week average across entire treatment period
Company: Response assessed at week 12 (last 4 weeks), based on clinical expert opinion that 85% of experts agreed on 12-week assessment
ERG: Response should be based on 12-week average over entire treatment period, for consistency with NMA definition and with trial data showing early improvements
Committee: 12-week average across entire treatment period for consistency across all model inputs
ICER impact: uncertain_direction
Timing of when NMA-derived comparative benefit should be applied in the economic model
Company: Option 1: Apply full 12-week benefit from baseline at week 4
ERG: Option 2: Use benefit observed before week 12 for responders, applied at week 4 using alternative regression allowing incremental improvements weeks 1-12
Committee: Option 2 was most appropriate method to apply, allowing for incremental improvements between weeks 1 to 12
ICER impact: increases
Timing of applying network meta-analysis (NMA) results in the economic model. Company initially applied full benefit from week 9-12; ERG and committee favoured earlier application
Company: Option 1: Apply full 12-week benefit from baseline at week 4. This was preferred by company in original base case
ERG: Option 2: Use benefit observed before week 12 for responders, applied at week 4. Allows for incremental improvements weeks 1-12 using alternative regression. ERG had concerns about MMD data for non-responders with option 1
Committee: Option 2, applying incremental benefits between weeks 1-12 rather than applying full benefit at week 4
ICER impact: uncertain_direction
Baseline EQ-5D utility values differed between treatment arms at baseline despite randomisation
Company: Used regression model with treatment arm and MMD as covariates; rimegepant baseline utility (0.6136) was higher than placebo (0.5976), p=0.1436
ERG: Baseline mapped EQ-5D scores should be included as covariate in regression to ensure baseline utilities are similar between arms
Committee: Baseline mapped EQ-5D values for each treatment arm should be the same; agreed with ERG's approach
ICER impact: increases
Baseline utility values: Company derived utilities by mapping MSQ-v2 from BHV3000-305 trial to EQ-5D using regression adjusted for treatment arm and MMD count
Company: Baseline utility values at 0.6136 for rimegepant (n=348) and 0.5976 for placebo (n=346), difference not statistically significant (p=0.1436). Include treatment arm in regression model
ERG: Baseline utilities favoured rimegepant which could bias downstream comparisons. Prefer including baseline mapped EQ-5D as covariate to ensure treatment arms have same baseline utility
Committee: Baseline mapped EQ-5D values for each treatment arm should be the same; agreed with ERG's approach of including baseline scores as covariate
ICER impact: decreases
Evidence gaps
Commercial arrangement
Special considerations
Cross-references