CurrentmhnPolicy CP.PMN.261

Dichlorphenamide (Keveyis) Clinical Policy

Defines medical necessity criteria, prior-authorization requirements, dosing limits, continuation criteria, contraindications, and related administrative guidance for dichlorphenamide (Keveyis) across Commercial, HIM, and Medicaid lines of business.

Policy Summary

Payermhn

PolicyDichlorphenamide (Keveyis) Clinical Policy

Policy CodePolicy CP.PMN.261

Change TypeCoverage criteria revised; generic requirement added

Effective Date03.01.21

Next Review Date

Key ActionProvider must submit documentation (office chart notes, lab results, or other clinical information) that member meets all approval criteria.

POLICY UPDATE CHANGES

Initial approval duration revised from 3 months to 2 months to align with prescribing information recommending evaluation after 2 months.

Added Medicaid line of business.

Added requirement for use of generic for brand Keveyis requests.

Initial approval duration listed as 2 months (approval duration changed).

Continuation approval duration set to 12 months with requirement to document response.

3FDA-approved indications

18+Minimum age (years)

200 mg/dayMaximum daily dose

2 months

Initial approval duration

12 monthsContinuation approval duration

Coverage Summary

Coverage stance: covered_with_criteria. Scope summary: Defines medical necessity criteria, prior-authorization requirements, dosing limits, continuation criteria, contraindications, and related administrative guidance for dichlorphenamide (Keveyis) across Commercial, HIM, and Medicaid lines of business. Subject: Dichlorphenamide (Keveyis). Status: CURRENT. Effective date: 2021-03-01. Last review date: 2025-02-25.

FDA-approved indications: primary hyperkalemic periodic paralysis, primary hypokalemic periodic paralysis, and related variants (per FDA labeling).

Key thresholds and policy durations

Minimum age≥ 18 years

Maximum daily dose200 mg/day (4 tablets)

Initial approval duration2 months

Continuation approval duration12 months

Initial Therapy Criteria

Initial Approval Criteria

Keveyis is medically necessary when ALL of the following are met:

Initial Approval Criteria - Hyperkalemic/Hypokalemic Periodic Paralysis and Variants

Diagnosis of primary hyperkalemic or hypokalemic periodic paralysis, or related variants (i.e., Andersen's syndrome, paramyotonia congenita)
Age ≥ 18 years≥ 18 years
Prior therapy: Failure of acetazolamide at up to maximally indicated dose, unless contraindicated or clinically significant adverse effects are experienced
Brand vs generic requirement: If request is for brand Keveyis, member must use generic dichlorphenamide, unless contraindicated or clinically significant adverse effects are experienced

Continuation Therapy Criteria

Continuation (Renewal) Criteria

For continued therapy ALL of the following must be met:

Continuation (Renewal) Criteria - Hyperkalemic/Hypokalemic Periodic Paralysis and Variants

Continuity of care / prior authorization history: Member meets one of the following: (a) Currently receiving medication via Centene benefit or member has previously met initial approval criteria; OR (b) Member is currently receiving medication and is enrolled in a state and product with continuity of care regulations (refer to state specific addendums CC.PHARM.03A and CC.PHARM.03B)
Evidence of response: Member is responding positively to therapy as evidenced by reduced frequency of paralysis
Brand vs generic requirement: If request is for brand Keveyis, member must use generic dichlorphenamide, unless contraindicated or clinically significant adverse effects are experienced

Unapproved Indications / Exclusions

Diagnoses/Indications Not Authorized

Coverage is NOT authorized for:

Diagnoses/Indications Not Authorized: Non-FDA approved indications, which are not addressed in this policy, unless there is sufficient documentation of efficacy and safety according to the off-label use policies CP.CPA.09 (commercial), HIM.PA.154 (health insurance marketplace), and CP.PMN.53 (Medicaid), or evidence of coverage documents.

Provider Actions

Prior Authorization

Prior Authorization Required

Prior authorization is required for Keveyis (dichlorphenamide). All requests are subject to the policy's approval criteria and must be reviewed and approved prior to coverage.

Requests will be reviewed against the criteria in this policy (Initial and Continuation Therapy sections)
Approval is not guaranteed — medical necessity per policy must be met

Documentation Required

Submit documentation supporting criteria

Submit documentation supporting that the member has met all approval criteria. Acceptable documentation includes, but is not limited to, office chart notes, relevant laboratory results, and prior medication history.

Applicable / Related Policy Codes

References to related policiesmixed

CP.CPA.190	No coverage criteria policy for commercial (referenced for label changes/non-formulary handling)
HIM.PA.33	No coverage criteria policy for health insurance marketplace
CP.PMN.255	No coverage criteria policy for Medicaid
HIM.PA.103	Non-formulary policy for health insurance marketplace
CP.PMN.16	Non-formulary policy for Medicaid
CP.CPA.09	Off-label use policy for commercial
HIM.PA.154	Off-label use policy for health insurance marketplace
CP.PMN.53	Off-label use policy for Medicaid
CC.PHARM.03A	State-specific continuity of care addendum A
CC.PHARM.03B	State-specific continuity of care addendum B

Clinical Evidence

Key evidence cited in the policy includes randomized trials and reviews: Tawil R et al., Ann Neurol 2000;47:46-53; reviews by Venance SL et al., Brain 2006; and Statland JM et al., Muscle Nerve 2018.

Clinical reference: Keveyis Prescribing Information, August 2024.

Background

Dichlorphenamide (Keveyis) is an oral carbonic anhydrase inhibitor available as 50 mg tablets.

Keveyis is FDA-approved for the treatment of primary hyperkalemic periodic paralysis, primary hypokalemic periodic paralysis, and related variants.

Per the prescribing information, initial dosing can start at 50 mg PO once daily or twice daily with titration at weekly intervals based on response up to a maximum recommended daily dose of 200 mg/day. The PI recommends that prescribers evaluate the patient’s response after 2 months of treatment to determine whether therapy should be continued.

Clarification: 'Variants of periodic paralysis' includes paramyotonia congenita and Andersen syndrome.

Revision History

12.15.20revised

Initial approval duration revised from 3 months to 2 months to align with prescribing information recommending evaluation after 2 months.

08.22.23added

Added requirement that requests for brand Keveyis must use generic dichlorphenamide unless contraindicated or clinically significant adverse effects are experienced.

12.15.20added

Policy created; adopted from CP.PCH.04 and Medicaid line of business was added.

Policy Summary

Payermhn

PolicyDichlorphenamide (Keveyis) Clinical Policy

Policy CodePolicy CP.PMN.261

Change TypeCoverage criteria revised; generic requirement added

Effective Date03.01.21

Next Review Date

Key ActionProvider must submit documentation (office chart notes, lab results, or other clinical information) that member meets all approval criteria.

On This Page

Dose limit: Dose does not exceed 200 mg (4 tablets) per day≤ 200 mg/day

Approval duration: 2 months

Initial Approval — Other diagnoses/indications

If the request is not for the FDA-approved indications above, meet ONE of the following:

Recent label change: If this drug has recently (within the last 6 months) undergone a label change (e.g., newly approved indication, age expansion, new dosing regimen) that is not yet reflected in this policy, refer to the relevant formulary/no-coverage or non-formulary policy for the applicable line of business: CP.CPA.190 (commercial), HIM.PA.33 (health insurance marketplace), CP.PMN.255 (Medicaid) for formulary/no-coverage; or CP.CPA.190 (commercial), HIM.PA.103 (health insurance marketplace), CP.PMN.16 (Medicaid) for non-formulary policies.
Off-label referral: If the requested use (e.g., diagnosis, age, dosing regimen) is NOT specifically listed under section III AND the label-change condition does not apply, refer to the off-label use policy for the relevant line of business: CP.CPA.09 (commercial), HIM.PA.154 (health insurance marketplace), CP.PMN.53 (Medicaid).

Dose increase limit: If request is for a dose increase, new dose does not exceed 200 mg (4 tablets) per day≤ 200 mg/day

Approval duration: 12 months

Office/clinic notes documenting diagnosis and clinical course

Relevant lab results (e.g., potassium levels if applicable)

Medication history documenting prior trials (e.g., acetazolamide) and reasons for failure or intolerance

Documentation Required

Evidence of response required for continuation

For continuation/renewal requests, provide evidence of a positive clinical response to therapy. Documentation should demonstrate reduced frequency of paralysis or other objective improvement attributable to dichlorphenamide.

Documentation of clinical response since initiation (e.g., decreased frequency/severity of paralysis episodes)
If requesting a dose increase, documentation that new dose will not exceed 200 mg/day

Billing Rule

Brand vs Generic Requirement

If the request is for brand Keveyis, the member must use generic dichlorphenamide unless the generic is contraindicated or causes clinically significant adverse effects. This requirement applies to both initial and continuation requests.

Applies to initial approval requests
Applies to continuation/renewal requests

clarifiedLatest

Continuation approval duration set to 12 months with requirement to document positive response to therapy.