CurrentNeighborhood Health Plan of Rhode IslandPolicy N/A

Dichlorphenamide (Keveyis) prior authorization for periodic paralysis

Policy governs authorization, continuation, quantity limits, and coverage duration for dichlorphenamide for treatment of primary hypokalemic and hyperkalemic periodic paralysis for Medicaid members.

Policy Summary

PayerNeighborhood Health Plan of Rhode Island

PolicyDichlorphenamide (Keveyis) prior authorization for periodic paralysis

Policy CodePolicy N/A

Change TypeNo material changes

Effective DateAug 1, 2019

Next Review DateN/A

Key ActionObtain neurologist prescription or consultation and document age ≥18, diagnostic support, prior acetazolamide failure/intolerance, and maximum daily dose ≤200 mg.

SourceLink

POLICY UPDATE CHANGES

No material clinical or coverage changes in this revision.

2 moinitial authorization duration

12 morenewal authorization duration

≤200 mg/daydose limit

4 tabs/dayquantity limit

≥18age requirement

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Coverage Criteria for Dichlorphenamide (Keveyis)

Initial Therapy

Authorization of 2 months may be granted when ALL of the following are met:

Initial criteria: Patient is 18 years of age or older; Medication is prescribed by, or in consultation with a neurologist; Maximum daily dose does not exceed 200mg; Patient does not have hepatic impairment, metabolic acidosis, severe pulmonary disease (e.g., severe COPD), and is not concomitantly taking high‑dose aspirin (doses >325 mg/day); Patient has an inadequate treatment response, intolerance, or contraindication to acetazolamide.

Primary Hypokalemic Periodic Paralysis diagnosis support: Diagnosis must be supported by at least one: (a) genetic test results; (b) family history of primary hypokalemic periodic paralysis; OR (c) attacks associated with hypokalemia AND both Andersen‑Tawil syndrome and thyrotoxic periodic paralysis have been ruled out.

Supports initial coverage for hypokalemic form.

Primary Hyperkalemic Periodic Paralysis diagnosis support: Diagnosis must be supported by at least one: (a) genetic test results; (b) family history of primary hyperkalemic periodic paralysis; OR (c) attacks associated with hyperkalemia AND Andersen‑Tawil syndrome has been ruled out.

Supports initial coverage for hyperkalemic form.

Continuation Therapy

Authorization of 12 months may be granted when ALL of the following are met:

Continuation criteria: Medication is prescribed by, or in consultation with a neurologist; Maximum daily dose does not exceed 200mg; Patient has a documented diagnosis of primary hyperkalemic periodic paralysis, primary hypokalemic periodic paralysis, or related variants; Patient does not have hepatic insufficiency (e.g., Child‑Pugh Class A); Patient does not have severe pulmonary disease (e.g., severe COPD); Patient has a positive clinical response to the medication as evidenced by reduced frequency of paralysis and continues to require ongoing therapy.

Coverage is not supported for patients with hepatic impairment or hepatic insufficiency, metabolic acidosis, or severe pulmonary disease such as severe COPD; these conditions are exclusionary for both initial and continuation authorization. Requests will also be denied when the member is taking high‑dose aspirin (greater than 325 mg/day). These restrictions align with the policy’s safety-based contraindications and are required to be absent for approval.

The policy requires members to be 18 years of age or older for initial authorization; use in patients under 18 is not supported. In addition, the policy enforces a maximum permitted dosing threshold: the maximum daily dose is 200 mg. Requests that exceed this dose or are for patients younger than 18 are not eligible under the criteria.

Provider Requirements, Documentation, and Denial Triggers

Prior Authorization

Initial authorization requirements

Initial authorization: Authorization of up to 2 months may be granted when ALL criteria are met.

Patient is >= 18 years of age
Medication is prescribed by, or in consultation with, a neurologist
Maximum daily dose does not exceed 200 mg
Patient does not have hepatic impairment, metabolic acidosis, severe pulmonary disease (e.g., severe COPD), and is not concomitantly taking high‑dose aspirin (>325 mg/day)
Patient has an inadequate treatment response, intolerance, or contraindication to acetazolamide

Documentation Required

Renewal authorization requirements

Renewal / continuation authorization: Authorization of 12 months may be granted when ALL criteria are met.

Medication is prescribed by, or in consultation with, a neurologist
Maximum daily dose does not exceed 200 mg
Documented diagnosis of primary hyperkalemic periodic paralysis, primary hypokalemic periodic paralysis, or related variants
Patient does not have hepatic insufficiency (e.g., not Child‑Pugh Class B/C) and does not have severe pulmonary disease (e.g., severe COPD)
Patient demonstrates a positive clinical response (reduced frequency of paralytic attacks) and continues to require ongoing therapy

Step Therapy

Step therapy requirement

Step therapy requirement: prior to approval, there must be evidence that acetazolamide was tried and produced inadequate response, intolerance, or is contraindicated.

Documented inadequate response, intolerance, or contraindication to acetazolamide is required for initial authorization

Denial Risk

Triggers for denial

Triggers for denial: authorization may be denied if any of the following apply.

Patient is < 18 years of age
Prescriber is not a neurologist and no neurologist consultation is documented
Requested daily dose exceeds 200 mg
Presence of hepatic impairment or insufficiency
Metabolic acidosis documented
Severe pulmonary disease (e.g., severe COPD)
Concomitant use of high‑dose aspirin (>325 mg/day)
No documentation of inadequate response/intolerance/contraindication to acetazolamide when required
No documented diagnosis supporting primary hyperkalemic or hypokalemic periodic paralysis (see genetic testing, family history, or attack-associated electrolyte abnormalities with exclusion of Andersen‑Tawil and/or thyrotoxic periodic paralysis as applicable)

Diagnostic Support for Periodic Paralyses

Primary hypokalemic periodic paralysis — diagnostic support

Genetic testingDiagnosis may be supported by genetic test results.

Family historyDiagnosis may be supported by a family history of primary hypokalemic periodic paralysis.

Clinical attacks with hypokalemiaDiagnosis may be supported by attacks associated with hypokalemia provided both Andersen-Tawil syndrome and thyrotoxic periodic paralysis have been ruled out.

Primary hyperkalemic periodic paralysis — diagnostic support

Genetic testingDiagnosis may be supported by genetic test results.

Family historyDiagnosis may be supported by a family history of primary hyperkalemic periodic paralysis.

Clinical attacks with hyperkalemiaDiagnosis may be supported by attacks associated with hyperkalemia provided Andersen-Tawil syndrome has been ruled out.

Background and Indication

Dichlorphenamide (Keveyis) is used to reduce the frequency of paralysis episodes in patients with primary hypokalemic and primary hyperkalemic periodic paralysis. Per the policy, treatment must be prescribed by or in consultation with a neurologist and is intended for patients who have had an inadequate response to, intolerance of, or a contraindication to acetazolamide. Approved use requires diagnostic support for the specific periodic paralysis disorder and absence of exclusionary conditions, and continuation authorization requires demonstration of a positive clinical response (reduced frequency of paralysis) with ongoing need for therapy.