CurrentNeighborhood Health Plan of Rhode IslandPolicy N/A

Dichlorphenamide (Keveyis) coverage for periodic paralysis

Covers initial and continued authorization criteria, 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) coverage for periodic paralysis

Policy CodePolicy N/A

Change TypeNo material change

Effective DateAug 1, 2019

Next Review DateN/A

Key ActionObtain prior authorization with neurologist involvement and document inadequate response or intolerance to acetazolamide.

SourceLink

POLICY UPDATE CHANGES

No material clinical or coverage changes in this revision.

Initial 2 monthsauthorization duration for new starts

Renewal 12 monthsauthorization duration for continuation

200 mg/daymaximum daily dose

4/dayquantity limit (50 mg tablets)

Medicaidpayer scope

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Coverage Criteria

Initial Therapy

Covered when ALL of the following are met:

Initial authorization general 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 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 acetazolamideage >=18; dose <=200 mg/day

Supported by chunk 0

Primary Hypokalemic Periodic Paralysis diagnostic support: Diagnosis supported by at least one of: genetic test results; family history of primary hypokalemic periodic paralysis; attacks associated with hypokalemia AND both Andersen‑Tawil syndrome and thyrotoxic periodic paralysis have been ruled out1 of 3

Supported by chunk 1

Primary Hyperkalemic Periodic Paralysis diagnostic support: Diagnosis supported by at least one of: genetic test results; family history of primary hyperkalemic periodic paralysis; attacks associated with hyperkalemia AND Andersen‑Tawil syndrome has been ruled out1 of 3

Supported by chunk 2

Continuation Therapy

Covered 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 200 mg; 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 evidenced by reduced frequency of paralysis and continues to require ongoing therapydose <=200 mg/day

Supported by chunk 3

Patients with hepatic impairment or insufficiency, metabolic acidosis, or severe pulmonary disease (e.g., severe COPD) are excluded from coverage. Requests for patients who are concomitantly taking high‑dose aspirin (doses greater than 325 mg/day) are also not eligible. These contraindications apply to both initial and continuation authorizations and may result in denial if present.

Provider Actions & Authorization Procedures

Prior Authorization

Prior authorization durations

Initial authorization: 2 months when all initial criteria are met. Renewal authorization: 12 months when continuation criteria are met.

Initial authorization duration: 2 months
Renewal authorization duration: 12 months

Step Therapy

PROVIDER ACTIONS — Acetazolamide requirement

Patient must have inadequate response, intolerance, or contraindication to acetazolamide prior to approval.

Requirement to try/consider acetazolamide prior to approval unless inadequate response, intolerance, or contraindication documented

Documentation Required

PROVIDER ACTIONS — Documentation requirements

Documentation must support the diagnosis with one or more of the following depending on the clinical subtype: genetic test results, family history, or biochemical association (attacks associated with hypo- or hyperkalemia) and exclusion of alternate diagnoses where specified.

For primary hypokalemic periodic paralysis: genetic test results OR family history OR attacks associated with hypokalemia AND Andersen-Tawil syndrome and thyrotoxic periodic paralysis ruled out
For primary hyperkalemic periodic paralysis: genetic test results OR family history OR attacks associated with hyperkalemia AND Andersen-Tawil syndrome ruled out

Denial Risk

PROVIDER ACTIONS — Denial/limit conditions

Denial or limit conditions: requests exceeding 200 mg/day, lack of neurologist prescribing or consultation, patients with hepatic impairment/insufficiency, severe pulmonary disease (e.g., severe COPD), or concomitant high-dose aspirin (>325 mg/day) increase risk of denial.

Requests exceeding maximum daily dose of 200 mg
Medication not prescribed by or in consultation with a neurologist
Patients with hepatic impairment or insufficiency
Patients with severe pulmonary disease (e.g., severe COPD)
Concurrent use of high‑dose aspirin (greater than 325 mg/day)

Background

Dichlorphenamide is indicated to reduce the frequency of paralysis in patients with primary hypokalemic or primary hyperkalemic periodic paralysis. Treatment must be prescribed by, or in consultation with, a neurologist. Initial use requires that the patient be ≥18 years and have tried and had an inadequate response to, intolerance of, or a contraindication to acetazolamide. For continued therapy, the patient must have a documented diagnosis of primary hyperkalemic or hypokalemic periodic paralysis (or related variant) and demonstrate a positive clinical response to dichlorphenamide, evidenced by a reduced frequency of paralysis and ongoing need for therapy.

Definitions

Primary Hypokalemic Periodic Paralysis — Diagnostic criteria (supportive)

Diagnostic support — genetic testingDiagnosis supported by genetic test results

Diagnostic support — family historyPatient has a family history of primary hypokalemic periodic paralysis

Diagnostic support — biochemical associationAttacks associated with hypokalemia AND both Andersen-Tawil syndrome and thyrotoxic periodic paralysis have been ruled out

Specialist involvementMedication prescribed by or in consultation with a neurologist (required for authorization)

Primary Hyperkalemic Periodic Paralysis — Diagnostic criteria (supportive)

Diagnostic support — genetic testingDiagnosis supported by genetic test results

Diagnostic support — family historyPatient has a family history of primary hyperkalemic periodic paralysis

Diagnostic support — biochemical associationAttacks associated with hyperkalemia AND Andersen-Tawil syndrome has been ruled out