Personalised testing to find out if beta-blocker symptoms in heart failure are real or nocebo

pErsonalised Nocebo Assessment of Beta-blockEr Symptoms in Heart Failure

Not applicable Interventional Imperial College London · NCT07029906

This project will test a personalised sequence of low-dose bisoprolol, matched placebo, and no-pill weeks to see if people with HFrEF who stopped beta-blockers are experiencing true drug side effects or expected nocebo symptoms.

Quick facts

PhaseNot applicable
Study typeInterventional
Enrollment150 (estimated)
Ages18 Years and up
SexAll
SponsorImperial College London Academic / other
Locations1 site (London)
Trial IDNCT07029906 on ClinicalTrials.gov

What this trial studies

ENABLE-HF is a prospective, randomised N-of-1 design enrolling people with HFrEF (LVEF <40%) who previously stopped a beta-blocker because of perceived symptoms. After screening, participants complete a two-week open-label run-in of bisoprolol 2.5 mg, followed by a nine-week double-blind phase of three randomized weeks each of bisoprolol 2.5 mg, matched placebo, and no tablet, and finish with a two-week open-label bisoprolol period. Medication packs and a smartphone (if needed) are provided and weekly symptom data are collected during each phase. The design aims to compare symptom rates within each participant to determine whether symptoms recur on active drug but not on placebo or no-pill weeks.

Who should consider this trial

Good fit: Adults with HFrEF (LVEF <40%) who are not currently taking a beta‑blocker because they previously stopped it due to perceived side effects and who have no contraindications to bisoprolol are ideal candidates.

Not a fit: People with clear contraindications to beta‑blockers (for example severe asthma, marked bradycardia or high‑grade heart block), very limited life expectancy, or who cannot participate in the dosing and follow‑up schedule are unlikely to benefit.

Why it matters

Potential benefit: If successful, the approach could help many patients restart life‑prolonging beta‑blocker therapy by distinguishing true side effects from nocebo or disease‑related symptoms.

How similar studies have performed: Placebo‑controlled work has shown many perceived beta‑blocker symptoms occur at similar rates on placebo, and N‑of‑1 approaches have been used in other nocebo and symptom contexts, but this personalised protocol for HFrEF is relatively novel.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Heart failure with index LVEF \<40%
* Not currently taking beta-blocker tablets
* Previously tried one of beta-blocker tablet, and stopped taking it due to symptoms attributed to the beta-blocker
* Consenting to participate in the study

Exclusion Criteria:

* Documented anaphylaxis to beta-blockers
* Clinical contraindication to Bisoprolol including (but not limited to):

  1. Asthma requiring BTS treatment step 3 or higher
  2. Marked bradycardia (\<50 bpm)
  3. Symptomatic hypotension (systolic BP \<85mmHg)
  4. Metabolic acidosis
  5. Phaeochromocytoma
  6. 1st degree heart block with PR interval \>250ms
  7. 2nd degree or complete heart block
  8. Sick sinus syndrome
  9. Acute pulmonary oedema
* Life expectancy \<1 year
* Patient refusal or inability to participate in the study

Where this trial is running

London

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions Side-EffectHeart FailureSide-effectBeta-blockerNoceboHeart Failure Reduced Ejection FractionHFrEF
Last reviewed 2026-06-13 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.