CurrentmhnPolicy CP.PHAR.209

Aztreonam (Cayston) inhaled therapy for cystic fibrosis

Defines medical necessity and prior authorization criteria for inhaled aztreonam (Cayston) for members (HIM, Medicaid) when used for cystic fibrosis with Pseudomonas aeruginosa and guidance for continued therapy and other indications.

Policy Summary

Payermhn

PolicyAztreonam (Cayston) inhaled therapy for cystic fibrosis

Policy CodePolicy CP.PHAR.209

Change TypeCoverage criteria update

Effective Date05.01.16

Next Review Date

Key ActionProvider must submit documentation (office notes, lab results, airway culture showing Pseudomonas aeruginosa, antibiotic susceptibility testing, and evidence of failed tobramycin when applicable) to support criteria.

SourceLink

POLICY UPDATE CHANGES

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

Updated prescriber restriction to include 'expert in treatment of cystic fibrosis' in addition to pulmonologist and infectious disease specialist.

Added Kitabis Pak to the list of preferred tobramycin inhalation agents for step therapy.

225Maximum daily dose

28/28Dosing cycle

6 moInitial authorization length

12 moRenewal authorization length

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Medical Necessity Criteria

Initial therapy — Cystic Fibrosis

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

ALL of the following

Diagnosis of cystic fibrosis (CF)
Prescribed by or in consultation with a pulmonologist, infectious disease specialist, or an expert in treatment of cystic fibrosis
Age ≥ 6 years≥ 6 years
Pseudomonas aeruginosa present in at least one airway culture
One of:
- Failure of inhaled tobramycin (Kitabis Pak, TOBI, TOBI Podhaler are preferred) unless contraindicated or clinically significant adverse effects are experienced
  Prior authorization may be required for inhaled tobramycin; for Illinois HIM requests, the step therapy requirement does not apply per IL HB 5395
- Antibiotic susceptibility testing indicates that aztreonam would be more effective than tobramycin
If Cayston is prescribed concurrently (or for alternating use) with inhaled tobramycin, documentation supports inadequate response to either agent alone (e.g., deteriorating pulmonary status, recurrent pulmonary exacerbations)
Dose does not exceed 225 mg per day administered on a 28 days on/28 days off cycle≤ 225 mg/day; 28 days on / 28 days off

Initial therapy — Other diagnoses/indications

If the requested use is not FDA-approved and not listed in exclusions, follow formulary/non-formulary/off-label policies:

ANY of the following

If drug has had a recent label change not reflected in this policy, follow the appropriate formulary or non-formulary policy for the relevant line of business (e.g., HIM.PA.33, CP.PMN.255, HIM.PA.103, CP.PMN.16)
If requested use is not listed under 'Diagnoses/Indications for which coverage is NOT authorized' and no label-change exception applies, refer to the off-label use policy for the relevant line of business (HIM.PA.154 or CP.PMN.53)

Continued therapy — Cystic Fibrosis

Continued therapy is authorized when ALL of the following are met:

ALL of the following

One of:
- Member currently receiving medication via Centene benefit or member has previously met initial approval criteria
- Member is currently receiving medication and is enrolled in a state/product with continuity of care regulations (see state addendums CC.PHARM.03A and CC.PHARM.03B)
Member is responding positively to therapy as evidenced by reduction in respiratory symptoms (e.g., cough, wheezing, sputum production, or pulmonary exacerbations due to Pseudomonas aeruginosa)
If Cayston is prescribed concurrently (or for alternating use) with inhaled tobramycin, documentation supports inadequate response to either agent alone (e.g., deteriorating pulmonary status, recurrent pulmonary exacerbations)

Diagnoses/Indications Not Authorized

Coverage is not authorized for:

ALL of the following

Non‑FDA approved indications not addressed in this policy unless sufficient documentation of efficacy and safety is provided per off‑label use policies (HIM.PA.154 or CP.PMN.53)

Codes and Billing References

HCPCS / Billing code referencedHCPCS

J7699

Not otherwise classified drugs, inhalation solution administered through DME (informational)

What Providers Must Do

Prior Authorization

Prior authorization required

Prior authorization may be required for Cayston and/or inhaled tobramycin. The prior authorization request must document the prescriber's specialty (pulmonologist, infectious disease specialist, or an expert in treatment of cystic fibrosis) and provide clinical justification that the member meets the policy criteria for aztreonam therapy.

Affected billing code: J7699 (NOC drugs, inhalation solution administered through DME)

Documentation Required

Submit supporting documentation

Submit supporting clinical documentation with the prior authorization including office/chart notes and relevant laboratory data to demonstrate that the member meets all approval criteria for Cayston.

Office chart notes or clinical progress notes
Lab results and airway culture demonstrating Pseudomonas aeruginosa

Clinical Background

Aztreonam (Cayston) is an inhaled monobactam antibacterial approved to improve respiratory symptoms in cystic fibrosis (CF) patients with Pseudomonas aeruginosa (FDA indication). Safety and effectiveness are not established in pediatric patients under 7 years, in patients with FEV1 < 25% or > 75% predicted, or in patients colonized with Burkholderia cepacia. To limit resistance, Cayston should be used only in patients known to have airway Pseudomonas aeruginosa.

Per the policy, Cayston for CF must be prescribed by or in consultation with a pulmonologist, infectious disease specialist, or an expert in treatment of cystic fibrosis, and is intended for patients age ≥ 6 years with at least one airway culture positive for Pseudomonas aeruginosa. Dosing for CF is 75 mg inhaled three times daily (up to a maximum of 225 mg/day) given on a 28 days on / 28 days off cycle. Prior authorization is required and documentation should include airway culture results, antibiotic susceptibility testing, and evidence of prior tobramycin failure when applicable.

Limitations on use and clinical guidance note that aztreonam is recommended by the American Thoracic Society for chronic use in both mild and moderate-to-severe CF lung disease. The policy also addresses concurrent or alternating use with inhaled tobramycin: when Cayston is used with or alternated with tobramycin, documentation must support an inadequate response to either agent alone (for example, deteriorating pulmonary status or recurrent pulmonary exacerbations). For Illinois HIM requests, the policy includes a step therapy bypass for the tobramycin failure requirement effective 1/1/2026 per IL HB 5395.

Defined Terms

Definitions

CFCystic fibrosis

FEV1Forced expiratory volume in one second

Policy Updates

2025-04-09addedLatest

Added step therapy bypass for Illinois HIM requests per IL HB 5395 (effective 1/1/2026); step therapy requirements do not apply to Illinois HIM as noted in the criteria and coding revision.

2023-05-05revised

Updated prescriber restriction to include 'expert in treatment of cystic fibrosis' in addition to pulmonologist and infectious disease specialist to align with other inhaled antibiotic policies.

2024-05-09revised

Added Kitabis Pak to the list of preferred tobramycin inhalation agents for step therapy (clarification of preferred inhaled tobramycin products).

Age and Dosing Limits

Thresholds & dosing metrics

Minimum age≥ 6 years

Maximum daily dose≤ 225 mg/day

Dosing cycle28 days on / 28 days off

Initial authorization lengthApproval duration: 6 months (initial)

Renewal authorization lengthApproval duration: 12 months (continued)

Aztreonam (Cayston) inhaled therapy for cystic fibrosis

Medical Necessity Criteria

Codes and Billing References

What Providers Must Do

Clinical Background

Defined Terms

Policy Updates

Cross‑References

Age and Dosing Limits