CurrentmhnPolicy CP.PMN.261

Dichlorphenamide (Keveyis)

Defines medical necessity criteria, prior authorization requirements, quantity and dosing limits, continuation criteria, contraindications, and alternative therapies for dichlorphenamide (Keveyis) for commercial, HIM and Medicaid lines of business affiliated with Centene.

Policy Summary

Payermhn

PolicyDichlorphenamide (Keveyis)

Policy CodePolicy CP.PMN.261

Change TypeAdded generic requirementIL step therapy bypassquantity limit

Effective Date03.01.21

Next Review Date

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

SourceLink

POLICY UPDATE CHANGES

Added requirement for use of generic for brand Keveyis requests.

Added step therapy bypass for IL HIM per IL HB 5395.

Added requirement that request does not exceed health plan-approved quantity limit.

Multiple annual reviews with 'no significant changes'; references reviewed and updated.

3FDA approved indications

≥18Minimum age

200 mgMax daily dose

2 mo

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12 moContinued approval

Coverage Summary

coverage_stance: covered_with_criteria; policy_number: CP.PMN.261; effective: 03.01.21; last_review: 02.26.

scope_summary: Defines medical necessity criteria, prior authorization requirements, quantity and dosing limits, continuation criteria, contraindications, and alternative therapies for dichlorphenamide (Keveyis) for Commercial, HIM, and Medicaid lines of business affiliated with Centene.

subject: Dichlorphenamide (Keveyis) coverage policy.

Indications covered: primary hyperkalemic periodic paralysis, primary hypokalemic periodic paralysis, and related variants including paramyotonia congenita and Andersen syndrome.

Minimum age for coverage: ≥ 18 years.

I. Initial Therapy Criteria

I. Initial Approval Criteria - Hyperkalemic/Hypokalemic Periodic Paralysis and Variants

must meet all

ALL of the following

Diagnosis of primary hyperkalemic or hypokalemic periodic paralysis, or related variants (i.e., Andersen's syndrome, paramyotonia congenita)
Age ≥ 18 years
Step therapy (acetazolamide): Failure of acetazolamide at up to maximally indicated dose, unless contraindicated or clinically significant adverse effects are experienced
Per policy: step therapy bypass for Illinois HIM as of 2026-01-01 per IL HB 5395
Generic before brand: If request is for brand Keveyis, member must use generic dichlorphenamide, unless contraindicated or clinically significant adverse effects are experienced
Quantity limit: Request does not exceed health plan-approved quantity limit, if applicable
Dose limit: Dose does not exceed 200 mg (4 tablets) per day<= 200 mg/day

I.B Other diagnoses/indications

must meet one of

ANY of the following

Formulary/No coverage guidance: If drug has had a label change within last 6 months not yet reflected in this policy, follow referenced formulary/no coverage or non-formulary policies (CP.CPA.190, HIM.PA.33, CP.PMN.255, HIM.PA.103, CP.PMN.16) as applicable
Off-label policy referral: If requested use is not specifically listed under section III and criterion above does not apply, refer to off-label use policy for relevant line of business (CP.CPA.09, HIM.PA.154, CP.PMN.53)

II. Continuation Therapy Criteria

II. Continued Therapy - Hyperkalemic/Hypokalemic Periodic Paralysis and Variants

must meet all

ALL of the following

Continuity of care/previous approval: Member meets one of: (a) currently receiving medication via Centene benefit or previously met initial approval criteria; OR (b) currently receiving medication and enrolled in state/product with continuity of care regulations (refer to state specific addendums CC.PHARM.03A and CC.PHARM.03B)
Clinical response: Member is responding positively to therapy as evidenced by reduced frequency of paralysis
Prescribers should evaluate response after 2 months to decide on continuation
Generic before brand: If request is for brand Keveyis, member must use generic dichlorphenamide, unless contraindicated or clinically significant adverse effects are experienced

III. Diagnoses/Indications Not Authorized

ALL of the following

Not authorized: Non-FDA approved indications not addressed in this policy are not authorized unless sufficient documentation of efficacy and safety per off-label use policies or evidence of coverage documents
Refer to off-label use policies CP.CPA.09, HIM.PA.154, CP.PMN.53

Provider Actions / Prior Authorization

Prior Authorization

Prior authorization required

Prior authorization is required through Centene benefit processes. Requests must meet the policy's medical necessity criteria in order to be approved.

Documentation Required

Submission of supporting documentation

Provider must submit supporting documentation such as office chart notes, laboratory results, or other clinical information that demonstrates the member meets all approval criteria.

Office chart notes
Lab results
Other clinical information

Applicable Codes

Product availability (NDC not specified)NDC

No codes listed

Clinical Evidence

1Key RCTs (supports efficacy) - Ann Neurol 2000 randomized trials

Jul 2025Prescribing info date - Keveyis Prescribing Information (Taro)

2 moInitial evaluation period - prescribers should evaluate response after 2 months

Key randomized trials: Randomized trials of dichlorphenamide in the periodic paralyses (Tawil R et al., Ann Neurol 2000;47:46-53) support efficacy.

Prescribing information: Keveyis Prescribing Information, Taro Pharmaceuticals, July 2025.

Background

Background: Dichlorphenamide (Keveyis) is an oral carbonic anhydrase inhibitor indicated for primary hyperkalemic periodic paralysis, primary hypokalemic periodic paralysis, and related variants including paramyotonia congenita and Andersen syndrome.

Prescriber guidance: Per the Keveyis prescribing information, prescribers should evaluate the patient's response after 2 months of treatment to decide whether Keveyis should be continued.

Definitions — Variants: Includes paramyotonia congenita and Andersen syndrome; related genetic/clinical variants of periodic paralysis.

Revision History

08.22.23material change - added

Added requirement for use of generic for brand Keveyis requests; incorporated into initial and continued therapy sections.

11.06.25material change - added (1Q 2026 annual review)Latest

1Q 2026 annual review: added step therapy bypass for IL HIM per IL HB 5395 (bypass effective 01.01.2026) and added requirement that request does not exceed health plan-approved quantity limit; P&T Approval Date = 02.26.

2021-2025

Policy Summary

Payermhn

PolicyDichlorphenamide (Keveyis)

Policy CodePolicy CP.PMN.261

Change TypeAdded generic requirementIL step therapy bypassquantity limit

Effective Date03.01.21

Next Review Date

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

SourceLink

On This Page

Quantity limit: Request does not exceed health plan-approved quantity limit, if applicable

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

II.B Continued Therapy - Other diagnoses/indications

must meet one of

ANY of the following

Formulary/No coverage guidance: If drug has had a label change within last 6 months not yet reflected in this policy, follow referenced formulary/no coverage or non-formulary policies (CP.CPA.190, HIM.PA.33, CP.PMN.255, HIM.PA.103, CP.PMN.16) as applicable
Off-label policy referral: If requested use is not specifically listed under section III and criterion above does not apply, refer to off-label use policy for relevant line of business (CP.CPA.09, HIM.PA.154, CP.PMN.53)

Step Therapy

Step therapy requirement (acetazolamide)

Step therapy with acetazolamide is required prior to approval of Keveyis unless acetazolamide is contraindicated or causes clinically significant adverse effects. For Illinois HIM requests, the step therapy requirement is bypassed effective 2026-01-01 per IL HB 5395.

Failure of acetazolamide at up to maximally indicated dose required unless contraindicated or adverse effects occur
IL HIM bypass effective 2026-01-01 per IL HB 5395

Billing Rule

Generic required before brand

Requests for brand Keveyis require use of the generic dichlorphenamide unless the generic is contraindicated or causes clinically significant adverse effects.

Billing Rule

Quantity and dose limits

Dose must not exceed 200 mg per day and the request must not exceed the health plan–approved quantity limit. Initial approvals are for 2 months; continued approvals are for 12 months.

Maximum dose: ≤ 200 mg/day (4 tablets)
Initial approval duration: 2 months
Continued approval duration: 12 months
Request must not exceed health plan–approved quantity limit

non-material revision

Regular reference updates and template changes; multiple annual reviews with 'no significant changes'.