Gepants for Prevention
Gepants are small-molecule CGRP receptor antagonists that offer oral migraine prevention — bridging the gap between traditional oral preventives (tolerability issues, slow titration) and CGRP monoclonal antibodies (injections, IV infusions). Two gepants are approved for prevention: atogepant (daily) and rimegepant (every other day). Unlike the mAbs, gepants are metabolized hepatically and have drug interaction potential, but they offer the convenience of an oral pill with a CGRP-specific mechanism.
Bottom Line
- Atogepant (Qulipta): FDA-approved for both episodic and chronic migraine prevention. Taken daily. Strongest preventive efficacy data among oral gepants.
- Rimegepant (Nurtec ODT): FDA-approved for both acute treatment and prevention. Taken every other day for prevention. The only dual-use agent (acute + preventive).
- Efficacy: Monthly migraine day reduction of ~2-4 days vs placebo; comparable to CGRP mAbs in indirect comparisons
- Hepatotoxicity: No signal in trials, but earlier gepants were discontinued for liver toxicity — periodic LFT monitoring is reasonable
- After CGRP mAb failure: Gepants may still work — different binding kinetics and potential CNS penetration
- For breakthrough attacks: Use a triptan or ubrogepant (if on atogepant) or triptan only (if on rimegepant)
Mechanism
Gepants competitively antagonize the CGRP receptor (CLR/RAMP1 complex), blocking CGRP signaling at both peripheral and central sites. Unlike the mAbs, gepants are small molecules (~500-600 Da) that can cross the blood-brain barrier to some degree, potentially providing both peripheral and central CGRP blockade.
Key pharmacologic differences from CGRP mAbs:
- Reversible binding — short half-lives (6-11 hours for rimegepant, ~11 hours for atogepant) vs 27-32 days for mAbs
- Hepatic metabolism — CYP3A4 substrate (both agents); drug interactions with strong CYP3A4 inhibitors/inducers
- Daily/EOD dosing required for preventive effect (no depot effect)
- Potential CNS penetration — may provide central effects that large mAbs cannot
Atogepant (Qulipta)
Dosing
| Indication | Dose | Frequency |
|---|---|---|
| Episodic migraine prevention | 10 mg, 30 mg, or 60 mg | Once daily |
| Chronic migraine prevention | 60 mg | Once daily |
| With strong CYP3A4 inhibitors | 10 mg | Once daily |
| With strong CYP3A4 inducers | Avoid concomitant use | — |
ADVANCE (Episodic Migraine)
Ailani et al., NEJM 2021: 910 patients with episodic migraine (4-14 migraine days/month), randomized to atogepant 10 mg, 30 mg, 60 mg daily, or placebo for 12 weeks.
- Change in monthly migraine days: -3.7 (10 mg), -3.9 (30 mg), -4.2 (60 mg) vs -2.5 placebo (p<0.001 for all doses)
- Placebo-subtracted difference: -1.2 to -1.7 days depending on dose
- ≥50% responder rate: 56% (10 mg), 59% (30 mg), 61% (60 mg) vs 29% placebo
- Benefit seen as early as week 1 across all doses
PROGRESS (Chronic Migraine)
Pozo-Rosich et al., NEJM 2023: 778 patients with chronic migraine (≥15 headache days/month), randomized to atogepant 60 mg daily or placebo for 12 weeks.
- Change in monthly migraine days: -7.5 vs -5.1 placebo (difference: -2.4 days, p<0.001)
- ≥50% responder rate: 41% vs 26% placebo (p<0.001)
- Effective regardless of medication overuse status
- Benefit sustained through 12 weeks with no tachyphylaxis
ADVANCE and PROGRESS: Key Takeaways
- 60 mg showed the most consistent benefit across both EM and CM — this is the go-to dose for most patients
- 10 mg is reasonable for patients on strong CYP3A4 inhibitors or those who prefer the lowest effective dose
- The -2.4 day advantage over placebo in CM (PROGRESS) is comparable to CGRP mAb CM trials
- No signal for hepatotoxicity (ALT >3x ULN: <1% in both arms)
Long-Term and Comparative Data
Open-Label Extension of ADVANCE: Atogepant 60 mg daily for up to 40 additional weeks.
- Sustained reduction in monthly migraine days through 52 weeks total
- No new safety signals; treatment-emergent adverse events similar to the 12-week trials
- No evidence of MOH with daily gepant use
Atogepant vs Topiramate (Ailani et al., Lancet Neurol 2024): 341 patients with episodic migraine who had failed 2-4 prior preventive classes were randomized to atogepant 60 mg daily or oral topiramate (titrated to 50-100 mg/day) for 24 weeks.
- Change in monthly migraine days: -4.2 (atogepant) vs -2.9 (topiramate) over 24 weeks
- ≥50% responder rate: 58% vs 38% (p<0.001)
- Discontinuation due to AEs: 6% (atogepant) vs 26% (topiramate)
- Key result: Atogepant was both more effective and far better tolerated than topiramate in treatment-experienced patients
Rimegepant (Nurtec ODT)
Dosing
- Acute treatment: 75 mg as needed (max one dose per day)
- Prevention: 75 mg every other day
- Dual use: Patients taking rimegepant EOD for prevention should not take an additional dose on off-days for acute treatment (use a triptan or other acute agent instead)
Prevention Trial
Croop et al., Lancet 2021: 747 patients with episodic migraine (4-14 migraine days/month), randomized to rimegepant 75 mg every other day or placebo for 12 weeks.
- Change in monthly migraine days: -4.3 vs -3.5 placebo (difference: -0.8 days, p=0.0099)
- ≥50% responder rate: 49% vs 41% placebo (p=0.025)
- Moderate effect size but statistically significant
Rimegepant for Prevention: Context
- The treatment effect over placebo (-0.8 days) is smaller than atogepant or CGRP mAbs. The high placebo response (3.5 days) narrowed the gap.
- The main advantage is dual-use flexibility — one drug for both prevention and acute treatment
- Best suited for patients with moderate frequency episodic migraine who want a single oral agent for both roles
- No CM-specific prevention trial exists for rimegepant (it is approved for EM prevention only)
Acute Treatment While on Preventive Gepant
Patients on preventive gepants will still have breakthrough migraines. Here's how to manage acute treatment:
| Preventive Gepant | Acute Treatment Options | Avoid |
|---|---|---|
| Atogepant (daily) | Triptans, ubrogepant, rimegepant, NSAIDs, lasmiditan | No specific restrictions |
| Rimegepant (EOD prevention) | Triptans, NSAIDs, lasmiditan | Additional rimegepant on "off" days; avoid ubrogepant (same class, limited data) |
Practical Approach to Breakthrough Attacks
- If on atogepant: Triptans remain first-line for acute treatment. Ubrogepant or rimegepant can also be used (different gepant, PRN dosing).
- If on rimegepant EOD: Use a triptan for breakthrough attacks. Do NOT take extra rimegepant on off-days — this exceeds the studied preventive dosing and approaches acute overuse.
- For triptan-ineligible patients on atogepant: Ubrogepant or lasmiditan are reasonable acute options.
- Track acute medication days: Even on preventive therapy, keep acute medications to <10 days/month to avoid MOH.
Patients Who Failed CGRP mAbs
Can a gepant work if a CGRP mAb failed? Yes, potentially.
- Different binding kinetics: Gepants have reversible, competitive binding vs the tight, prolonged binding of mAbs. Some patients may respond better to intermittent receptor blockade.
- CNS penetration: Gepants cross the BBB to some extent; mAbs do not. Central CGRP blockade may provide additional benefit in some patients.
- Real-world evidence: Case series report ~30-40% of CGRP mAb non-responders have meaningful improvement with atogepant
- Practical approach: If a patient failed 1-2 CGRP mAbs, trying atogepant is reasonable before abandoning the CGRP pathway entirely
Switching Scenarios
- mAb → Gepant: Can start gepant immediately when mAb is due (no washout needed). There will be overlap of CGRP blockade for ~1 month.
- Gepant → mAb: Can start mAb immediately; gepant will wash out within 48 hours.
- One gepant → Another gepant: Limited data, but switching from rimegepant to atogepant (or vice versa) is occasionally tried for non-responders.
Gepant + CGRP mAb Combination
Combining a preventive gepant with a CGRP mAb is not routinely recommended but is occasionally considered in refractory cases:
- Same pathway: Both block CGRP signaling; theoretical concern for additive CGRP-blocking side effects (constipation, potential cardiovascular effects)
- No efficacy data: No trials have studied combining preventive gepants with CGRP mAbs; unknown if there is additive benefit
- Cost: Both are expensive; insurance unlikely to cover combination
- Exception: Using an acute gepant (ubrogepant) while on a CGRP mAb is well-supported — the COURAGE trial showed high efficacy and satisfaction
🔴 Gepant + mAb: Current Guidance
- Preventive gepant + CGRP mAb: Not recommended as standard practice; no additive efficacy data; potential for increased side effects
- Acute gepant + CGRP mAb: Acceptable — COURAGE supports ubrogepant use for breakthrough attacks in patients on CGRP mAbs
- If a patient is refractory to both classes separately, combination with onabotulinumtoxinA (different mechanism) is preferred over gepant + mAb
Safety
Common Side Effects
| Side Effect | Atogepant | Rimegepant |
|---|---|---|
| Nausea | 5-7% | ~2% |
| Constipation | 6-7% | ~1% |
| Fatigue | 3-5% | ~2% |
| Decreased appetite | 2-4% | Rare |
| Hypersensitivity reactions | Rare | Reported (rash, dyspnea) |
Hepatotoxicity
- First-generation gepants (telcagepant, MK-3207) were abandoned due to hepatotoxicity in trials
- Atogepant and rimegepant: No hepatotoxicity signal in clinical trials or post-marketing surveillance to date
- However, given class history, baseline LFTs and periodic monitoring are reasonable (not mandated by label)
- Avoid in severe hepatic impairment (Child-Pugh C)
Drug Interactions
🔴 CYP3A4 Interactions
- Strong CYP3A4 inhibitors (ketoconazole, itraconazole, clarithromycin, HIV protease inhibitors): Reduce atogepant to 10 mg daily; avoid rimegepant or limit to no more than once every 48 hours
- Strong CYP3A4 inducers (rifampin, carbamazepine, phenytoin, St. John's wort): Avoid concomitant use with both gepants — significantly reduces drug levels
- Moderate CYP3A4 inhibitors (fluconazole, erythromycin, diltiazem, verapamil, grapefruit juice): Reduce atogepant to 30 mg daily; no specific adjustment for rimegepant but use caution
- OATP1B1/1B3 inhibitors (cyclosporine, single-dose rifampin): Reduce atogepant to 10 mg daily
Choosing Between Gepants and CGRP mAbs
| Factor | Gepants (Atogepant/Rimegepant) | CGRP mAbs |
|---|---|---|
| Route | Oral (daily or EOD) | SC monthly/quarterly or IV quarterly |
| Adherence | Requires daily/EOD pill compliance | Monthly or quarterly injection — easier adherence |
| Washout | Fast (hours) — favorable in pregnancy planning | Slow (5+ months) |
| Drug interactions | Yes (CYP3A4) | None |
| Hepatic concern | Theoretical (class history); avoid in severe liver disease | None |
| Dual acute + preventive | Rimegepant only | No |
| Needle aversion | Not an issue | Barrier for some patients |
| Insurance access | Often fewer prior-auth hurdles than mAbs | Often requires 2+ oral preventive failures |
| After mAb failure | May still work (different kinetics, CNS penetration) | Switch within class or to gepant |
Practical Recommendations
- Prefer atogepant when you need robust oral preventive efficacy, especially in CM or patients who failed topiramate
- Prefer rimegepant for moderate-frequency EM patients who want a single agent for both acute and preventive use
- Prefer CGRP mAbs for patients with adherence concerns, drug interaction issues, or liver disease
- After CGRP mAb failure: Try atogepant before abandoning the CGRP pathway (~30-40% may still respond)
- Gepants can be combined with onabotulinumtoxinA (different mechanism)
- Women planning pregnancy: Gepants are advantageous over mAbs due to rapid washout (<48 hours vs months)
Pipeline: Zavegepant for Prevention
Zavegepant (intranasal) is currently approved only for acute migraine treatment, but preventive trials are underway:
- Phase 3 trials evaluating zavegepant nasal spray for migraine prevention are ongoing
- Potential advantage: nasal route may offer faster onset for both acute and preventive use
- If approved, would be the third gepant with preventive indication
Trial Comparison Table
| Trial | Year | Agent | Population | Key Outcome |
|---|---|---|---|---|
| ADVANCE | 2021 | Atogepant 10/30/60 mg daily | Episodic migraine (n=910) | MMD: -3.7 to -4.2 vs -2.5; 50% RR: 56-61% vs 29% |
| PROGRESS | 2023 | Atogepant 60 mg daily | Chronic migraine (n=778) | MMD: -7.5 vs -5.1; 50% RR: 41% vs 26% |
| Atogepant vs Topiramate | 2024 | Atogepant 60 mg vs topiramate | EM, 2-4 prior failures (n=341) | 50% RR: 58% vs 38%; AE discontinuation: 6% vs 26% |
| Rimegepant Prevention | 2021 | Rimegepant 75 mg EOD | Episodic migraine (n=747) | MMD: -4.3 vs -3.5; 50% RR: 49% vs 41% |
| Ubrogepant for Acute Migraine | 2019 | Ubrogepant 50/100 mg | Acute migraine (n=1672) | 2h pain-free: 19-21% vs 12% placebo |
| COURAGE | 2023 | Ubrogepant + CGRP mAb | CM on CGRP mAb (n=813) | 70-73% satisfied; confirms acute gepant + mAb safety |
References
- Ailani J, et al. Atogepant for the preventive treatment of migraine (ADVANCE). N Engl J Med. 2021;385(8):695-706.
- Pozo-Rosich P, et al. Atogepant for the preventive treatment of chronic migraine (PROGRESS). N Engl J Med. 2023;388(12):1132-1142.
- Ailani J, et al. Atogepant versus oral standard of care for migraine prevention in participants with prior preventive treatment failures. Lancet Neurol. 2024.
- Croop R, et al. Efficacy, safety, and tolerability of rimegepant every other day for the preventive treatment of episodic migraine. Lancet. 2021;397(10268):51-60.
- Dodick DW, et al. Ubrogepant for the treatment of migraine (Ubrogepant for Acute Migraine). N Engl J Med. 2019;381(23):2230-2241.
- Ailani J, et al. Ubrogepant and CGRP mAb combination (COURAGE). Headache. 2023;63(5):611-621.
- Lipton RB, et al. Rimegepant, an oral calcitonin gene-related peptide receptor antagonist, for migraine. N Engl J Med. 2019;381(2):142-149.
- Goadsby PJ, Dodick DW. CGRP receptor antagonists (gepants) for migraine: pharmacology and clinical data. Cephalalgia. 2022;42(11-12):1213-1226.
