CurrentAvMedPolicy N/A

Dichlorphenamide (Keveyis) prior authorization

This form and policy govern prior authorization and step-edit requirements for coverage of dichlorphenamide (Keveyis) for AvMed members, including initial and reauthorization criteria and documentation requirements; applies to prescribers requesting pharmacy benefit coverage.

Policy Summary

PayerAvMed

PolicyDichlorphenamide (Keveyis) prior authorization

Policy CodePolicy N/A

Change TypeNo material change

Effective DateN/A

Next Review DateN/A

Key ActionPrescribing physician must sign the prior authorization request and fax it to 1-305-671-0200; initial authorization is for 12 months.

SourceLink

POLICY UPDATE CHANGES

No material clinical or coverage changes in this revision.

12 monthsInitial authorization duration

120/tab/30dQuantity limit

18+Minimum age

60 daysRequired acetazolamide trial

Coverage Criteria

inv-01: Initial Therapy

Policy Summary

PayerAvMed

PolicyDichlorphenamide (Keveyis) prior authorization

Policy CodePolicy N/A

Change TypeNo material change

Effective DateN/A

Next Review DateN/A

Key ActionPrescribing physician must sign the prior authorization request and fax it to 1-305-671-0200; initial authorization is for 12 months.

SourceLink

On This Page

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Age and prescriber: Member is 18 years of age or older AND prescribed by or in consultation with a neurologist or a physician who specializes in the care of individuals with primary periodic paralysis (e.g., muscle disease specialist, physiatrist).

Initial authorization 12 months

Diagnosis confirmation: Member has a diagnosis of primary periodic paralysis confirmed by BOTH genetic testing for confirmation of SCN4 or CACNA1S mutation AND electromyography confirming absence of myotonic discharges.

Provider must submit lab or chart note confirmation

Diagnostic support for subtype: For hypokalemic periodic paralysis: serum K < 3.5 mEq/L during attack OR family history of condition. For hyperkalemic periodic paralysis: serum K > 5.0 mEq/L during attack OR increase in serum K >1.5 mEq/L during attack OR family history of condition.

Provider must submit lab or chart note confirmation

Step therapy with acetazolamide: Member has had an inadequate response to a trial of acetazolamide at a dose of 125-1500 mg/day for at least 60 days within the year prior to request OR has a documented contraindication to acetazolamide (verification via chart notes or pharmacy paid claims). Inadequate response is defined as no reduction in number of attacks per month after treatment at recommended doses.>= 60 days within the year prior to request

Baseline and on-treatment attack frequency/severity must be documented; previous therapies will be verified through pharmacy paid claims or chart notes

Failure of nonpharmacologic measures: Member continues to have paralytic attacks despite dietary intervention and avoidance of triggers.

inv-02: Reauthorization

Reauthorization criteria — covered when ALL of the following are met

Clinical response: Member has experienced disease response as indicated by a decrease in the frequency and/or severity of attacks of muscle weakness from pre-treatment baseline.

Reauthorization 12 months; baseline and on-treatment attack frequency/severity must be submitted

Tolerability: Member has NOT experienced unacceptable toxicity from the drug (examples include hypersensitivity reactions, hypokalemia, metabolic acidosis, falls).

Initial Therapy

inv-14: Initial Therapy

Initial authorization criteria

Age and specialist: Member is >=18 years and prescribed by or in consultation with an appropriate specialist (neurologist or physician experienced in primary periodic paralysis).

Initial authorization 12 months

Diagnosis confirmation: Primary periodic paralysis confirmed by genetic testing for SCN4 or CACNA1S mutation AND EMG showing absence of myotonic discharges.

Chart or lab documentation required

Prior acetazolamide trial: Inadequate response to acetazolamide 125-1500 mg/day for >= 60 days within the past year OR documented contraindication to acetazolamide (verified by chart notes or pharmacy paid claims).>= 60 days within the year prior to request

Inadequate response defined as no reduction in attacks per month after acetazolamide at recommended doses; baseline and on-treatment attack frequency must be submitted

Continuation / Reauthorization

inv-15: Reauthorization

Reauthorization requirements

Response and safety: Member must have decreased frequency and/or severity of attacks from baseline AND must not have unacceptable toxicity from the drug (examples: hypersensitivity, hypokalemia, metabolic acidosis, falls).

Reauthorization interval 12 months; documentation including lab results, diagnostics, and chart notes must be provided or request may be denied

Provider Actions & Documentation

Prior Authorization

Prior Authorization Required

Prior authorization required. The prescribing physician must sign and clearly print their name on the prior authorization request (preprinted stamps are not valid). Fax the completed form to 1-305-671-0200. Initial authorization is for 12 months.

Fax: 1-305-671-0200
Initial authorization length: 12 months

Billing Rule

Quantity Limit

Quantity limit: 120 tablets per 30 days.

Quantity limit = 120 tablets / 30 days

Step Therapy

Step Therapy Requirement

Member must have had an inadequate response to acetazolamide 125–1500 mg/day for at least 60 days within the year prior to the request, OR have a documented contraindication to acetazolamide (verification via chart notes or paid pharmacy claims required). Inadequate response is defined as no reduction in number of attacks per month after treatment at recommended doses.

Acetazolamide trial: 125–1500 mg/day for ≥60 days within past 12 months OR documented contraindication
Inadequate response definition: no reduction in monthly attack frequency

Documentation Required

Required Documentation

Required documentation includes: prescriber signature, member and prescriber identifiers (AvMed #, DOB, prescriber name, DEA or NPI), office contact phone/fax, drug form/strength, dosing schedule, length of therapy, diagnosis and ICD code, weight and date, recommended dosage, and quantity requested. For clinical criteria, submit genetic testing results (SCN4A or CACNA1S), EMG results confirming absence of myotonic discharges, lab results or chart notes supporting serum potassium values during attacks or family history, baseline and on-treatment attack frequency/severity documentation, and proof of prior acetazolamide therapy or contraindication.

Prescriber signature (must be signed by prescribing physician; preprinted stamps not valid)
Member AvMed # and DOB; Prescriber name and DEA or NPI; Office contact name, phone, fax
Drug form/strength, dosing schedule, length of therapy, recommended dosage, quantity requested
Diagnosis and ICD code; weight and date
Genetic testing for SCN4A or CACNA1S mutation
EMG confirming absence of myotonic discharges
Lab/chart documentation of serum K during attacks or family history as applicable
Chart notes documenting baseline attacks/month prior to acetazolamide and baseline/on-treatment frequency and severity (required for renewal)
Documentation of acetazolamide trial (dosing and duration) or documented contraindication

Denial Risk

Incomplete or Incorrect Requests

Incomplete, incorrect, or illegible information (including missing signatures, contact information, or identifiers) can delay processing or result in denial of the authorization.

Ensure all fields are complete and legible to avoid delays or denial

Denial Risk

Missing Supporting Documentation

Failure to provide required supporting documentation — for example genetic testing, EMG results, lab values, chart notes, or prior therapy documentation — may result in denial of the request.

Missing genetic test results, EMG, serum potassium lab values, chart notes of baseline and treatment response, or documentation of prior acetazolamide trial may cause denial

Step	Requirement
1	Trial of acetazolamide 125–1500 mg/day for at least 60 days within the year prior to request unless there is a documented contraindication to acetazolamide; inadequate response is defined as no reduction in number of attacks per month after treatment at recommended doses (verification via chart notes or pharmacy paid claims).

Definitions

inv-12: Hypokalemic periodic paralysis

Diagnostic evidenceSerum K < 3.5 mEq/L during an attack

Alternative supportFamily history of hypokalemic periodic paralysis

Documentation requirementProvider must submit lab or chart note confirmation to support the finding

inv-13: Hyperkalemic periodic paralysis

Diagnostic evidenceSerum K > 5.0 mEq/L during an attack

Alternate lab criterionIncrease in serum K > 1.5 mEq/L during an attack

Alternative supportFamily history of hyperkalemic periodic paralysis

Documentation requirementProvider must submit lab or chart note confirmation to support the finding

Background

Primary periodic paralysis is a genetic channelopathy characterized by episodic attacks of muscle weakness associated with changes in serum potassium; dichlorphenamide (Keveyis) is indicated for prevention of attacks when acetazolamide is inadequate or contraindicated. Documentation to confirm diagnosis should include genetic testing and electromyography results, and subtype-specific laboratory evidence or family history (for example, serum potassium < 3.5 mEq/L during an attack supports hypokalemic periodic paralysis, while serum potassium > 5.0 mEq/L or an increase > 1.5 mEq/L during an attack supports hyperkalemic periodic paralysis).

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