CF Buyers Club · Treatment Access Guide

Triko Dose Sparing Guide

Elexacaftor / Tezacaftor / Ivacaftor

A practical guide to making treatment affordable

Why this guide exists

Triko & Bexdeco — generic versions of Trikafta & Kalydeco — are a potentially life-changing treatment for cystic fibrosis patients with responsive mutations (please check eligibility). Although these drugs are much cheaper than Trikafta, the cost and supply can still make access difficult. The normal dosage involves taking two Triko tablets in the morning and one Bexdeco tablet in the evening.

This guide explains a dose sparing approach pioneered by a team in South Africa who were searching for a solution for CF patients unable to afford modulators. This approach is based on prescribing guidance for Trikafta that can make treatment last longer and reduce overall cost. The study can be seen here.

Key point: Using this dosing strategy, no evening dose of Bexdeco (generic Kalydeco) is required.
1

Know your medication

Each Triko tablet contains

  • Elexacaftor 100 mg
  • Tezacaftor 50 mg
  • Ivacaftor 75 mg

Each Bexdeco tablet contains

  • Ivacaftor 150 mg

Manufacturer Beximco Pharmaceuticals sells pots of Triko and Bexdeco — each one contains 30 tablets. One pot of Triko costs $450 and one pot of Bexdeco costs $150.

The full dose for 30 days costs:

  • $1050 for children age 6–11 years weighing over 30 kg, and people age 12 years and older (2 pots of Triko plus 1 pot of Bexdeco), and
  • $525 for children aged 6–11 weighing less than 30 kg (1 pot of Triko plus 0.5 pot of Bexdeco)
2

How reduced dosing works

Triko is broken down by the liver enzyme CYP3A. A second medicine (a strong CYP3A inhibitor) slows this process so that:

  • Triko stays in your body much longer
  • You only need to take Triko twice per week instead of every day
  • No Bexdeco is needed
3

Choosing and taking your “booster” medicine

To make dose sparing of Triko work, you must take a strong CYP3A inhibitor every day. You will need a prescription and to obtain this medicine in your own country, so you will need to discuss this with your CF doctor.

Recommended option: Clarithromycin

Why this is recommended

  • It is the only medicine studied in published research using this approach
  • Widely available and generally low cost
  • Already used in some people with cystic fibrosis

Practical advantages

  • Easy to obtain in many countries
  • Familiar to clinicians
  • Can act as both an antibiotic and a “booster” for Triko

This guide follows the published study approach, which used clarithromycin.

4

Clarithromycin — weekly routine

Clarithromycin is taken every day (not just on Triko days).

Dose

Group Clarithromycin dose
Children age 6–11 over 30 kg
and people age 12 and older		 500 mg twice daily
(morning and evening)
Children age 6–11 under 30 kg 250 mg twice daily
(morning and evening)
5

Triko — weekly dose sparing routine

Choose 2 fixed days each week:

  • Example: Monday + Thursday
  • Always leave 3–4 days between doses

Rules

  • Morning only (Triko)
  • No evening doses (Bexdeco is not needed)
  • Same days every week
6

Full and dose sparing schedule & costs

Approximately 3 months supply. (This does not include potential shipping or any other associated costs.)

Triko & Bexdeco
~ three month supply		 Full dose Age 12+ & children 6–11 over 30 kg 2× Triko every morning
1× Bexdeco every evening 		Full dose Children 6–11 under 30 kg 1× Triko every morning
½ Bexdeco every evening 		Dose sparing Age 12+ & children 6–11 over 30 kg 4× Triko per week
No Bexdeco needed 		Dose sparing Children 6–11 under 30 kg 2× Triko per week
No Bexdeco needed
Triko (30 tablets per pot) 6 pots = $2700 3 pots = $1350 2 pots = $900 1 pot = $450
Bexdeco (30 tablets per pot) 3 pots = $450 1.5 pots = $225 Not needed Not needed
Strong CYP3A inhibitor Not taken Not taken Taken twice every day Taken twice every day
Total cost for ≥ 90 days $3150
(90 days)		 $1575
(90 days)
(Order 2 pots of Bexdeco = $1650)		 $900
(105 days)		 $450
(105 days)
  • No Bexdeco is needed for the dose sparing regimen.
  • For children aged 6–11, our medical expert has recommended that they start on the lower dose regardless of weight.

Important considerations to discuss with your clinician

  • Long-term use of clarithromycin may increase antibiotic resistance (CF patients routinely take long-term antibiotics to control infection, so the risks versus benefits should be considered).
  • Tell your doctor about:
    • Any side effects
    • Other medicines being taken

Alternative options

Ritonavir or Itraconazole

  • Also work as strong CYP3A inhibitors
  • May be considered if clarithromycin is unavailable or not suitable
  • However, they have not yet been studied in the same way for this specific strategy

Final note

This approach:

  • Is based on prescribing adjustments for Trikafta
  • Follows a published study using clarithromycin
  • Is being explored to improve affordability
  • Should be used with medical guidance and monitoring

Questions

If you have any further questions about the dose sparing strategy, please get in touch.

Email us Read the Buyers’ Club Handbook

This guide is for information only and is not a substitute for professional medical advice. Any change to treatment should be made with, and monitored by, your CF clinician.