Kalydeco (ivacaftor)
An approved treatment for Cystic Fibrosis.
The same compound appears under different names depending on the context. Here is how to identify Ivacaftor wherever you encounter it, plus the key facts at a glance.
- Generic name
- Ivacaftor
- Brand name
- Kalydeco
- Development code
- VX-770
- Drug class
- CFTR modulator (potentiator)
- Manufacturer
- Vertex Pharmaceuticals
- How it's taken
- Kalydeco tablets are taken twice daily with a fatty meal.
The first CFTR modulator approved for cystic fibrosis. A twice-daily pill for patients with gating mutations (like G551D) where the CFTR protein reaches the cell surface but doesn't open properly.
We'll email you when Kalydeco's FDA label changes, when the FDA acts on it, and when new trials for Cystic Fibrosis open. Unsubscribe anytime.
Where Ivacaftor fits
First CFTR modulator approved for CF. Now primarily used as monotherapy for patients with specific gating mutations who are not eligible for combination modulators, and as a component of Trikafta.
How Ivacaftor works
Kalydeco was the first medicine to target the root cause of cystic fibrosis. It works as a 'potentiator' that helps the CFTR protein work better by keeping the chloride channel open longer, allowing salt and water to flow properly and preventing thick, sticky mucus. Think of it as oiling a stuck door so it opens and stays open.
Mechanism: CFTR potentiator that opens the defective chloride channel
Side effects and safety
Common side effects include nausea, diarrhea, headache, and upper respiratory infections. Some people experience rashes. Avoid grapefruit juice. Watch for yellowing of skin or eyes, dark urine, or unusual tiredness as signs of liver problems. The label also warns about serious allergic reactions, including anaphylaxis, and about mood changes such as anxiety, depression, sleep problems and suicidal thoughts or behavior, which can start within the first 3 months; tell your care team right away if these happen. Raised pressure inside the skull (intracranial hypertension) has been reported with ivacaftor-containing medicines, so report an unusual headache or vision changes promptly. Strong CYP3A inducers such as rifampin or St. John's wort are not recommended with Kalydeco because they can make it less effective.
This is not a complete list of side effects. Talk to your doctor or pharmacist about what to expect and when to seek medical attention.
Taking Ivacaftor
Kalydeco tablets are taken twice daily with a fatty meal. For children aged 1 month to under 6 years, Kalydeco comes as oral granules that are mixed with 1 teaspoon (5 mL) of soft food or liquid. Treatment is long-term. Insurance covers it for patients with the G551D mutation or other specific mutations.
Availability and cost
Only available as the brand-name product.
First-in-class CFTR potentiator for patients with specific gating mutations. As the pioneering CFTR modulator for a rare genetic disease, it established specialty-tier pricing in the CF space.
Help paying for Kalydeco
Pick your insurance to see which help fits. Drugmaker copay cards can't be used with Medicare, Medicaid or TRICARE; charity funds are the usual route there.
- Copay help
Eligible patients with commercial insurance may pay as little as $0 per fill. Annual assistance up to $20,000. Not available with Medicare, Medicaid or TRICARE.
For: private insurance · source - Insurance and case manager help
A Support Specialist verifies insurance coverage and costs, helps explore financial assistance options regardless of insurance, and coordinates specialty pharmacy shipments and refills.
The official page does not say who qualifies. Ask the program. · source
Good to know: Vertex's official pages don't describe a free medicine program for uninsured patients; ask Vertex GPS about other options. Vertex's HCP FAQ says Support Specialists help patients with government insurance or no insurance 'explore alternative options.'
- From a charity · The Assistance FundCystic Fibrosis fundWaitlist
Pays for: Copays, coinsurance, deductibles and other health-related expenses.
The foundation says: “WAITLIST — Accepting Waitlist Patients. TAF is currently accepting requests to join the enrollment waitlist for this program. Waitlists a…”
Access and eligibility
Kalydeco is approved for patients age 1 month and older who have at least one ivacaftor-responsive CFTR mutation (a specific set of qualifying mutations). It is not recommended as monotherapy for patients homozygous for F508del.
Check eligibility toolSource: Kalydeco.com (Vertex Pharmaceuticals)
Access program details are provided for informational purposes and may vary based on insurance coverage, geographic location, and individual circumstances. Confirm current eligibility directly with the manufacturer or your specialty pharmacy.
Clinical trial results
FDA approved Kalydeco in January 2012. Phase 3 trials showed people with the G551D mutation had significant lung function improvements and were about half as likely to have pulmonary exacerbations (flare-ups of lung symptoms) through 48 weeks. This was the first medicine to target the underlying genetic defect of CF.
Development history
Vertex Pharmaceuticals developed ivacaftor after screening thousands of compounds and identifying VX-770 as a potentiator. The FDA reviewed it under priority review and approved it in just 3 months in January 2012. It paved the way for all later CF combination therapies.
Explore Cystic Fibrosis trials
Other Cystic Fibrosis treatments
Common questions about Ivacaftor
▸What is Ivacaftor (Kalydeco)?
The first CFTR modulator approved for cystic fibrosis. A twice-daily pill for patients with gating mutations (like G551D) where the CFTR protein reaches the cell surface but doesn't open properly.
▸How does Ivacaftor work?
Kalydeco was the first medicine to target the root cause of cystic fibrosis. It works as a 'potentiator' that helps the CFTR protein work better by keeping the chloride channel open longer, allowing salt and water to flow properly and preventing thick, sticky mucus. Think of it as oiling a stuck door so it opens and stays open.
▸What are the side effects of Ivacaftor?
Common side effects include nausea, diarrhea, headache, and upper respiratory infections. Some people experience rashes. Avoid grapefruit juice. Watch for yellowing of skin or eyes, dark urine, or unusual tiredness as signs of liver problems. The label also warns about serious allergic reactions, including anaphylaxis, and about mood changes such as anxiety, depression, sleep problems and suicidal thoughts or behavior, which can start within the first 3 months; tell your care team right away if these happen. Raised pressure inside the skull (intracranial hypertension) has been reported with ivacaftor-containing medicines, so report an unusual headache or vision changes promptly. Strong CYP3A inducers such as rifampin or St. John's wort are not recommended with Kalydeco because they can make it less effective.
▸How is Ivacaftor taken?
Kalydeco tablets are taken twice daily with a fatty meal. For children aged 1 month to under 6 years, Kalydeco comes as oral granules that are mixed with 1 teaspoon (5 mL) of soft food or liquid. Treatment is long-term. Insurance covers it for patients with the G551D mutation or other specific mutations.
▸Is Ivacaftor FDA approved?
Yes, Ivacaftor (Kalydeco) is FDA approved (2012) for the treatment of Cystic Fibrosis.
▸Why was Kalydeco considered revolutionary when it was approved?
Kalydeco was the first medicine ever to treat the underlying cause of cystic fibrosis rather than just managing symptoms. Before 2012, CF treatment focused entirely on airway clearance, antibiotics, and enzyme supplements. Kalydeco proved that correcting the defective CFTR protein was possible, opening the door for all subsequent CFTR modulators including Orkambi, Symdeko, Trikafta, and Alyftrek. It fundamentally changed how researchers and clinicians thought about treating genetic diseases.
▸What is a gating mutation and how does it relate to Kalydeco?
A gating mutation affects how the CFTR chloride channel opens and closes. In patients with gating mutations (like G551D), the CFTR protein reaches the cell surface but does not open properly, so chloride ions cannot flow through. Kalydeco acts as a potentiator, helping the channel stay open longer. Gating mutations are relatively rare, accounting for about 4-5% of CF patients, which is why Kalydeco as monotherapy treats a smaller population than combination modulators like Trikafta.
▸Can Kalydeco be used for babies?
Yes. Kalydeco is approved for patients as young as 1 month old who have ivacaftor-responsive mutations, making it the CF modulator with the youngest approved age range. Infant dosing uses a granule formulation mixed with soft food or liquid rather than tablets. Early initiation in infants aims to prevent organ damage before it starts, particularly pancreatic insufficiency and early lung changes.
▸Is Kalydeco still used now that Trikafta exists?
Yes, but for a narrower population. Kalydeco remains the preferred treatment for patients with gating mutations (like G551D) who only need a potentiator, not a corrector. It is also used as monotherapy for certain other responsive mutations where combination therapy is not needed or not approved. Additionally, ivacaftor is a component of Trikafta and Alyftrek, so patients on those combinations are already receiving it as part of their regimen. For babies under 1 year old, Kalydeco is the only approved CFTR modulator. Orkambi is approved from age 1 for children with 2 copies of F508del.
▸How quickly does Kalydeco work?
Patients with gating mutations often see rapid improvement. In clinical trials, significant increases in lung function (FEV1) were measurable within 2 weeks of starting treatment. Sweat chloride levels, a biomarker of CFTR function, also dropped substantially within the first few weeks. Many patients report feeling noticeably better in terms of energy and breathing within days to weeks of starting therapy.
▸What monitoring is needed while taking Kalydeco?
Liver function tests (ALT and AST) are recommended before starting, every 3 months for the first year, and annually thereafter. Eye exams are recommended at baseline and periodically during treatment, particularly in pediatric patients, because cataracts have been reported in animal studies and in some children taking ivacaftor. Your CF care team will set an appropriate monitoring schedule.