On placebos, placebo responses and placebo responders. (A review of psychological, psychopharmacological and psychophysiological factors). I. Psychological factors.
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Ethics↗
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Results for “Placebos”
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On placebos, placebo responses and placebo responders. A review of psychological, psychopharmacological and psychophysiological factors. II. Psychopharmacological and psychophysiological factors.
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Animals↗
Placebo response, placebo effect, and two attributes.
Two putative predictors of placebo response were studied in three samples of psychiatric outpatients. Two groups, 73 university medical center patients and 56 college health service patients, underwent 1 week of placebo treatment. A quasi-control group of 112 patients receiving no medication waited about 1 week before beginning psychotherapy. One attribute, acquiescence or traditionalism, predicted placebo response, thereby replicating prior findings. Acquiescence was unrelated to change in controls indicating that it may represent a correlate of true placebo effect under some conditions. Additional findings suggested qualifications as to the generality of the relationship. The second attribute, autonomic awareness, was associated with change in all three samples. It appeared to predict nonspecific improvement unrelated to placebo probably due to its relationship to intensity of somatization.
Adult↗
[On circadian variations of the placebo effect on the pain threshold of healthy teeth: Contribution to a physiology of placebo effects (author's transl)].
Placebo doses can influence the pain threshold of healthy teeth according to the label. Systematic longitudinal researches over the day with measuring the utilization time of cold stimulus on healthy front teeth demonstrate that the placebo effect is subject to significant circadian variations. During daytime a pseudo-analgesic causes a stronger and steeper onset of increase of the tooth pain threshold than during the night, when the pain threshold is influenced only minimal or even inverse. The placebo effect can come up to 40% of the pain threshold increase caused by a usual analgesic; this portion, however, is as well subject to high circadian variations. The extent of the placebo effect corresponds to the order of magnitude of the spontaneous circadian variations of pain threshold and correlates positively to it. These correlations are considered as indicating that those vegetative mechanisms causing the circadian variations of the pain threshold are equally involved in affecting the placebo actions.
Circadian Rhythm↗
O'Leary and Borkovec's conceptualization of placebo: the placebo paradox.
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Humans↗
[The placebo effect and placebo substances (pharmacological and therapeutic considerations)].
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Placebos↗
Dose-response effects of albuterol aerosol compared with isoproterenol and placebo aerosols: response to albuterol, isoproterenol, and placebo aerosols.
Albuterol aerosol was an effective bronchodilator as reflected by indices of pulmonary function obtained from spirometry and flow volume curves; Compared with isoproterenol, there were minimal side effects even at the highest doses, and bronchodilation lasted significantly longer. In addition albuterol was successfully used by a patient with idiopathic hypertrophic subaortic stenosis who was unable to tolerate isoproterenol, as well as by some patients with idiosyncratic responses to isoproterenol; A few patients appeared to derive little benefit from either albuterol or isoproterenol.
Adolescent↗
Role of pain in placebo analgesia.
The hypothesis that perceived pain intensity can influence placebo analgesia was tested. One hundred and seven subjects rated their pain from from 0 to 10 on a visual analog scale after a standard wisdom tooth extraction. The expected course of such postoperative pain in the absence of therapy or placebo is a steady increase; this was confirmed by blind administration of the placebo. When placebos were given intravenously in view of the patients, some (placebo nonresponders) reported that their pain increased, whereas others (placebo responders) reported that their pain either decreased or remained the same over the next 60 min. A placebo response was more likely to occur if the pain rating 5 min prior to placebo administration (initial pain) was greater than 2.6. Furthermore, placebo responders with initial pain above this 2.6 level reported significantly greater mean analgesia than those with lower initial pain. Indeed, responders with initial pain less than 2.6 reported no change in pain during the 60 min after administration of a placebo. When their initial pain level was greater than 2.6, they reported a steady decline in pain over this period. However, above the 2.6 level there was no obvious relationship between the magnitude of the placebo analgesia and the initial pain.
Analgesia↗
Placebo treatment in congestive heart failure.
In order to evaluate the effect of placebo treatment in congestive heart failure, we retrospectively studied 24 patients with moderately severe congestive heart failure who participated in heart failure treatment trials performed over the past 10 years in the Ohio State University Heart Failure Research Laboratory. Placebo-treated patients from 4 placebo-controlled trials comprised the placebo treatment group (n = 15), while one natural course-controlled trial provided patients for the non-placebo control group (n = 9). Changes in symptoms, left ventricular function and exercise duration were assessed following an 8-week course of therapy. Chronic placebo therapy resulted in an 81-second improvement in exercise duration which was statistically significant when compared to pretreatment baseline and to the duration achieved by the nonplacebo control group. Clinically, functional class improved significantly by 27% above baseline only for the placebo treatment group. Indices of left ventricular function did not change for either group. The salient feature of this study is that the placebo treatment effect, while believed to exist in congestive heart failure, has never been demonstrated in a manner which controlled for the natural course and variability of the disease process. The operative components of the placebo effect remain unknown, and further investigation will be necessary to elucidate the underlying mechanisms involved. However, the importance of this phenomenon lies not only with the response to and effects of placebo therapy but also in the role that the placebo effect plays in what is generally presumed to be the predominant responses, effects and benefits of active drug therapy.
Adult↗
Ivonescimab plus chemotherapy versus placebo plus chemotherapy in patients with advanced EGFR-mutated non-small-cell lung cancer after disease progression on EGFR tyrosine kinase inhibitor therapy (HARMONi): a multicentre, randomised, double-blind, phase 3 trial.
BACKGROUND: Ivonescimab has shown clinical efficacy in non-small-cell lung cancer (NSCLC). We aimed to assess the efficacy and safety of ivonescimab plus chemotherapy versus placebo plus chemotherapy in patients with advanced EGFR-mutated NSCLC whose disease progressed after third-generation EGFR tyrosine kinase inhibitor (TKI) therapy. METHODS: HARMONi is a randomised, placebo-controlled, double-blind, phase 3 trial done at 114 cancer centres and hospitals across Asia, Europe, and North America. Eligible patients were aged at least 18 years (upper limit: 75 years in Asia) with stage IIIB/IIIC or IV non-squamous EGFR-mutated NSCLC, disease progression after treatment with a third-generation EGFR-TKI, and an Eastern Cooperative Oncology Group performance status score of 0 or 1. Patients were randomly assigned (1:1) via a centralised interactive voice response system or interactive web response system to receive ivonescimab (20 mg/kg) or placebo plus pemetrexed (500 mg/m2) and carboplatin (target area under the curve 5 mg/mL per min) intravenously every 3 weeks. Randomisation was stratified by brain metastases status at enrolment and geographical region. The primary endpoints were progression-free survival by blinded independent radiology review committee and overall survival in the intention-to-treat population. Safety was assessed in patients who received at least one dose of trial treatment. This study is registered with ClinicalTrials.gov (NCT06396065), has completed enrolment, and is ongoing for treatment and follow-up. FINDINGS: From Jan 25, 2022, to Oct 1, 2024, 660 individuals were screened for eligibility; of these, 438 were enrolled and randomly assigned to receive ivonescimab plus chemotherapy or placebo plus chemotherapy (219 per group). Of enrolled patients, 257 (59%) were female and 181 (41%) were male; 306 (70%) reported race as Asian, and 105 (24%) as White. At a median follow-up of 22·3 months (95% CI 21·5-23·0), 275 progression or death events had occurred in 345 patients (129 events among 172 patients in the ivonescimab plus chemotherapy group and 146 events among 173 patients in the placebo plus chemotherapy group). Median progression-free survival was 6·8 months (95% CI 5·7-7·1) in the ivonescimab plus chemotherapy group versus 4·4 months (4·1-5·5) in the placebo plus chemotherapy group (hazard ratio [HR] 0·52; 95% CI 0·41-0·66; p<0·0001). At a median follow-up of 29·7 months (95% CI 27·7-31·0), 262 deaths occurred in 438 patients (122 in the ivonescimab plus chemotherapy group and 140 in the placebo plus chemotherapy group). Median overall survival was 16·8 months (14·3-19·0) in the ivonescimab plus chemotherapy group versus 14·0 months (12·8-15·7) in the placebo plus chemotherapy group (HR 0·79; 0·62-1·01). The most common grade 3-4 treatment-related adverse events in the ivonescimab plus chemotherapy versus the placebo plus chemotherapy group were decreased neutrophil count (42 [19%] of 218 vs 36 [17%] of 218), decreased white blood cell count (28 [13%] vs 24 [11%]), decreased platelet count (27 [12%] vs 14 [6%]), and anaemia (22 [10%] vs 27 [12%]). Serious treatment-related adverse events occurred in 61 (28%) patients in the ivonescimab plus chemotherapy group and 33 (15%) patients in the placebo plus chemotherapy group. Treatment-related adverse events led to death in four patients (disease progression, multiple organ dysfunction syndrome, and hepatic failure, each in one patient; gastrointestinal haemorrhage and pulmonary embolism in one patient) in the ivonescimab plus chemotherapy group and five patients (pneumonitis, myocardial infarction, cerebrovascular accident, cognitive disorder, and embolic stroke, each in one patient) in the placebo plus chemotherapy group. INTERPRETATION: Ivonescimab plus chemotherapy showed a clinically meaningful and statistically significant progression-free survival benefit in patients with EGFR-mutated NSCLC after progression on EGFR-TKI therapy. The clinical benefit and lack of new safety signals of ivonescimab with chemotherapy support the potential for the combination as a new treatment option in this patient population. FUNDING: Summit Therapeutics.
Humans↗
The current status of placebo in hospital practice.
Despite a voluminous literature on the topic of placebo, there has been little documentation of either actual clinical practice of prescribing placebo or the attitudes that surround it. Through a questionnaire survey of all head nurses of clinical units in one health services area of Connecticut, data were obtained on current practices regarding placebo use in the natural hospital setting. Multiple reasons for placebo use in the natural hospital setting. Multiple reasons for placebo use were given, and it was noted that patients receiving placebo tended to be viewed in certain ways. The effectiveness of placebo in symptom relief was reported as nearly double that reported in the experimental literature. Methodologic issues of the study and of placebo investigation, in general, are discussed. Because common clinical problems appear to generate most instances of placebo use, several issues pertinent to medical education are raised. Some future directions for placebo research are proposed.
Adolescent↗
[Exercise-induced asthma and placebos].
The effectiveness of a placebo in 15 patients with exercise-induced asthma (E.I.A., decrease of FEV1 by more than 10% after a standard run uphill on a treadmill) has been measured. 7 patients repeated the test without placebo protection, to separate the psychological effect of placebo from the emotional influences of the unusual environment of a technically highly developed hospital and adaptation to test procedures. On selection day FEV1 in % of preexercise value 10 min after exercise was 68.2 +/- 7.9% and on control day 67.1 +/- 9.5% (no statistical difference). The second stage comprised 14 patients who took the placebo or Cromolyn (Lomudal) before exercise; on selection day FEV1 in % of preexercise value 10 min after exercise was 70.1 +/- 4.8%; on placebo day it was 76.0 +/- 3.4% and on Cromolyn day 90.7 +/- 3.3%. There was statistically significant (p less than 0.025) protection by placebo. However, the protective effect of Cromolyn was much better than that of placebo (p less than 0.005). Placebo has a significantly greater protective effectiveness in E.I.A. than expected, and one much greater than previously suggested in preexisting asthma. As environmental influences were ruled out, the only explanation for the high degree of protection by placebo is the patients' trust in the placebo.
Adolescent↗
The glucagon and GLP-1 receptor dual agonist DD01 for metabolic dysfunction-associated steatotic liver disease and steatohepatitis (DD01-DN-02): 12-week results from a randomised, double-blind, multicentre, placebo-controlled, phase 2 trial.
BACKGROUND: Metabolic dysfunction-associated steatohepatitis (MASH) is a major public health problem arising in the context of metabolic syndrome and obesity. DD01 is a liver-targeted GLP-1 receptor and glucagon dual agonist being investigated for the treatment of metabolic dysfunction-associated steatotic liver disease (MASLD) and MASH. The DD01-DN-02 trial aimed to evaluate the efficacy and safety of DD01 in adults with MASLD or MASH; this initial analysis reports prespecified 12-week outcomes to assess early hepatic effects. METHODS: DD01-DN-02 is an ongoing, randomised, double-blind, multicentre, placebo-controlled, phase 2 trial conducted at 12 outpatient clinical sites in the USA. Adults aged 18-70 years with obesity or who were overweight (BMI ≥25 kg/m2) were included in the study. Patients with MASLD or MASH underwent liver biopsy and MRI-proton density fat fraction (PDFF) and were eligible if liver fat content was 10% or higher with metabolic risk factors, or if the biopsy confirmed MASH with a non-alcoholic fatty liver disease activity score of at least 4. Participants were randomly assigned (1:1) to receive once-weekly subcutaneous DD01 40 mg or matched placebo over 48 weeks, dose-escalated over 2 weeks, using a centrally administered interactive response technology system. The randomisation sequence was computer-generated by an independent statistician. Participants, investigators, study staff, outcome assessors, and the sponsor were masked to treatment assignment. The primary endpoint was the proportion of participants having at least a 30% relative reduction in liver fat by MRI-PDFF at week 12, which was analysed in all randomly assigned participants receiving at least one dose of study drug or placebo. Safety analyses included all participants who received at least one dose of study drug. Missing primary endpoint data were handled using multiple imputation under a missing-at-random assumption. This trial is registered with ClinicalTrials.gov (NCT06410924) and is ongoing but closed to new participants. FINDINGS: Between June 13, 2024, and Jan 30, 2025, 67 eligible participants were enrolled, of whom 33 were randomly assigned to DD01 and 34 to placebo. The mean age of participants was 48·4 years (SD 10·6), 42 (63%) were female, 25 (37%) were male, 57 (85%) were White, and 52 (78%) participants had biopsy-confirmed MASH. At week 12, 25 (76%) of 33 participants receiving DD01 had a 30% or higher reduction in liver fat versus four (12%) of 34 participants receiving placebo (adjusted common odds ratio 28·8 [95% CI 7·2-115·2]; adjusted relative risk 6·3 [95% CI 2·5-15·9]; p<0·0001). Treatment-emergent adverse events occurred in 28 (85%) of 33 participants receiving DD01 and 23 (68%) of 34 participants receiving placebo. The most common adverse events were nausea (18 [55%] of 33 participants assigned DD01; six [18%] of 34 participants assigned placebo), diarrhoea (nine [27%] of 33; six [18%] of 34), and vomiting (ten [30%] of 33; four [12%] of 34). Treatment-emergent adverse events led to treatment discontinuation in four (12%) of 33 participants in the DD01 group and one (3%) of 34 participants in the placebo group. Two (6%) treatment-emergent serious adverse events occurred in the DD01 group (abdominal pain and acute cholecystitis) and zero in the placebo group. No deaths occurred. INTERPRETATION: In this prespecified 12-week primary analysis, DD01 produced rapid reductions in liver fat compared with placebo, supporting further evaluation in long-term studies. FUNDING: D&D Pharmatech, Neuraly.
Humans↗
Placebo and its importance in medicine.
Placebo can be defined as "a therapeutic effect, drug or non-drug, or a part of it which, in the condition being treated, objectively does not have any specific pharmacodynamic action." Even today when powerful drugs are available placebo is important and present in therapy. Effective therapeutic agents are also sometimes used as placebo, mostly inadvertently. In clinical pharmacological investigations placebos are used deliberately to discriminate the pharmacodynamic action of drugs from psychic and other factors which can influence the objective of the drug evalution. The use of placebo in therapeutic trials is justified only when no effective treatment is available or the symptom or disease is trivial. Placebo effect is especially pronounced in diseases where pain is an important symptom as well as in psychosomatic diseases. The extent of placebo reaction depends on patient's characteristics (reactors and non-reactors), drug presentation, as well as on personality and attitudes of the prescriber. Deliberate use of placebo other than in clinical therapeutic investigation is justified in mild mental depression and in situations where the diagnosis is known, no drug is necessary, but the patient's pressure to get a prescription is irresistible (?). Every doctor should cultivate the induction of placebo reaction in treatment of his patient, but not to the extent that the belief of the former in the action of an inactive medication starts.
Ethics, Medical↗
β1- and β2-adrenergic Receptor Haplotypes Regulate Therapeutic Responses to Placebo and the Biased Ligand β-blocker Bucindolol.
BACKGROUND: ADRB1 and ADRB2, encoding cardiac myocyte β1- and β2-adrenergic receptors (ARs) that mediate pathologic myocardial remodeling in response to chronically increased signaling, contain N-terminus haplotype variants capable of influencing agonist- or biased ligand-induced receptor internalization that uncouples canonical signaling and initiates EGFR/ERK1/2 cardioprotection. METHODS: In two heart failure (HF) clinical trial genetic substudies we investigated effects of internalizing vs. internalization-resistant ADRB1/ADRB2 haplotypes on clinical or biomarker responses to the biased ligand β-blocker bucindolol vs. placebo or vs. the nonbiased β1-antagonist metoprolol, and in haplotyped isolated human heart preparations we measured ERK1/2 activation in response to these same interventions. RESULTS: In subjects with ≥3 internalizing ADRB1+ADRB2 haplotypes (6.7% subcohort) placebo treatment was associated with fewer clinical events compared to subjects with internalization-resistant haplotypes (Odds Ratio (OR) 0.28, 95% CI (0.10, 0.82)). In contrast, placebo treatment in subjects with ≥3 internalization-resistant haplotypes (70% subcohort) was associated with more clinical events in comparison to subjects with internalizing haplotype counterparts (OR 1.64 (1.46, 1.84)). Bucindolol treatment was equal to placebo in the ≥3 internalizing subcohort, but was superior to placebo in the internalization-resistant subcohort (bucindolol vs. placebo OR 0.49 (0.41, 0.58)). In subjects with all 4 haplotypes internalization-resistant (25% subcohort), bucindolol vs. placebo reduced time to first event rates by 62.3±17.5% (P <0.01, 1.68±0.34 fold > the all-haplotypes parent population and additive to 1.92±0.58 fold when the ADRB1 haplotype contained Arg389 rather than Gly389). The same bucindolol vs. placebo pattern was observed for NT-proBNP or norepinephrine reduction vs. metoprolol. In these comparisons ADRB2 and ADRB1 haplotypes behaved similarly, and although the haplotypes differed in frequency between Black and non-Black subjects, within haplotypes there were no by-race differences in therapeutic effects. Bucindolol but not metoprolol activated ERK1/2 signaling in isolated ventricular preparations with ≥3 internalization-resistant haplotypes. CONCLUSIONS: 1) Both β1- and β2-AR haplotypes regulate therapeutic responses in HF; internalizing species confer protection against clinical events in placebo-treated subjects, while in internalization-resistant haplotypes the biased ligand β-blocker bucindolol but not the non-biased ligand metoprolol is associated with favorable effects. 2) The biased ligand cardioprotective effect may be related to internalization-dependent or -independent ERK1/2 activation.
Beta Adrenergic Receptors↗
The mechanism of placebo analgesia.
The effect of naloxone on dental postoperative pain was studied to examine the hypothesis that endorphins mediate placebo analgesia. All patients had extraction of impacted mandibular third molars with diazepam, N2O, and local block with mepivacaine. 3 h and 4 h after surgery naloxone or a placebo was given under randomised, double-blind conditions. Pain was evaluated on a visual analogue scale. Patients given naloxone reported significantly greater pain than those given placebo. Patients given placebo as their first drug was either placebo responders, whose pain was reduced or unchanged, or nonresponders whose pain increased. Naloxone given as a second drug produced no additional increase in pain levels in nonresponders but did increase pain levels of placebo responders. Nonresponders had a final mean pain rating identical to that of responders who received naloxone as their second drug. Thus the enhancement of reported pain produced by naloxone can be entirely accounted for by its effect on placebo responders. These data are consistent with the hypothesis that endorphin release mediates placebo analgesia for dental postoperative pain.
Adolescent↗
Improved quality of life and prolonged survival with add-on homeopathic treatment in patients with non-small cell lung cancer: a prospective, randomized, placebo-controlled, double-blind, three-arm, multicenter study.
BACKGROUND: Alongside conventional anticancer treatment, add-on homeopathy might help to alleviate adverse effects of conventional therapy. AIM: The aim of this study was to replicate previous studies on the effect of adjunctive homeopathy on quality of life (QoL) and survival in non-small cell lung cancer (NSCLC) patients. METHOD: In this prospective, randomized, placebo-controlled, double-blind, three-arm multicenter phase III study with quadruple-checked data analysis, we investigated the potential effects of an add-on homeopathic treatment compared to placebo in patients with stage IV NSCLC in terms of QoL. Ninety-eight received either individualized homeopathic medicinal products (HMPs; n = 51) or placebo (n = 47) in a double-blinded fashion. Fifty-two control patients without homeopathic treatment were only observed in terms of their survival rate. The ingredients of the various HMPs were mainly prepared of plant, mineral, or animal origin. The data entry and statistical analysis were subject to an exceptional quadruple-checked data analysis process. The analysis presented in this article was inspired by our earlier report of this trial published in The Oncologist in 2020, which was retracted by that journal in November 2025 after two corrections; a majority of the co-authors disagreed with this decision. The present article is based on the same trial dataset but was deliberately designed to highlight the unique research methodology: design and preparation by a lead statistician, data entry, data clearing and independent statistical evaluation were performed in four mutually independent steps, reporting follows the CONSORT statement, and the interpretation of the findings has been reframed conservatively. RESULTS: Global health status (QoL) was higher in the homeopathy group than in the placebo group after 9 weeks and after 18 weeks (p < 0.001). With the exception of cognitive functioning at 9 weeks and of pain, diarrhea and financial difficulties at 9 weeks, all functional and symptom scales of the EORTC QLQ-C30 favored the homeopathy group (p < 0.001 for the multivariate comparisons), with between-group differences exceeding the threshold of 10 points that is generally regarded as clinically meaningful. Median survival time over the 730-day observation period was 435 days in the homeopathy group, 257 days in the placebo group (p = 0.010), and 228 days in the non-randomized control group (p < 0.001); the corresponding 2-year survival rates were 45.1%, 23.4%, and 13.5% (homeopathy vs. placebo p = 0.020; homeopathy vs. control p < 0.001). The difference between the placebo group and the non-randomized control group was not statistically significant (p = 0.154). CONCLUSION: In this trial, add-on homeopathy was associated with better quality of life across most functional and symptom domains, with clinically meaningful effect sizes congruently to a previous open study. Survival time was significantly longer in the homeopathy group compared to both the placebo and control groups. Independent replication, ideally within contemporary immuno-oncological treatment regimens is required. TRIALS REGISTRATION: ClinicalTrials.gov; No.: NCT01509612; January 7, 2012.
Humans↗
Efficacy and safety of mitapivat in adults with transfusion-dependent α-thalassaemia or β-thalassaemia (ENERGIZE-T): a double-blind, randomised, multicentre, placebo-controlled, phase 3 trial.
BACKGROUND: The absence of disease-modifying therapies for patients with α-thalassaemia and oral disease-modifying therapies for patients with β-thalassaemia has been a substantial unmet need in these patients. We assessed the efficacy and safety of mitapivat, an oral allosteric activator of pyruvate kinase, in adults with transfusion-dependent thalassaemia. METHODS: ENERGIZE-T is a global, double-blind, randomised, placebo-controlled, phase 3 trial, conducted across 19 countries in North America, Europe, Asia-Pacific, South America, and the Middle East. Patients aged 18 years or older with transfusion-dependent α-thalassaemia or β-thalassaemia were randomly allocated (2:1) with a central interactive response technology system, stratified by geographical region and thalassaemia genotype, to receive 100 mg mitapivat or placebo orally twice a day for 48 weeks. The primary endpoint was transfusion reduction response (TRR), defined as a reduction of at least 50% in transfused red blood cell units with a reduction of at least two units in any consecutive 12-week period until week 48 compared with baseline. Efficacy was analysed in the full analysis set, comprising all randomly allocated patients. Type, severity, and relationship of adverse events and serious adverse events were assessed in patients who received at least one dose of study treatment. This study is registered with ClinicalTrials.gov (NCT04770779) and is active but not recruiting. FINDINGS: Between Nov 30, 2021 and May 2, 2023, 305 patients were screened, of whom 258 were randomly allocated (median age 33·5 years [IQR 27·0-44·0]; 136 [53%] female and 122 [47%] male participants). Of 258 patients allocated, 238 (92%) completed the double-blind treatment period. All patients were required to have a safety follow-up approximately 4 weeks after the final dose of study drug, regardless of completion of the double-blind period or continuation into the open-label extension period. In the full analysis set, TRRs occurred in 52 (30%) of 171 patients in the mitapivat group and 11 (13%) of 87 in the placebo group (adjusted difference 18 percentage points [95% CI 8-27]; two-sided p=0·0003). The safety analysis set comprised 172 patients in the mitapivat group (including one patient allocated to the placebo group who received one dose of mitapivat in error) and 85 in the placebo group. Adverse events were reported in 155 (90%) patients treated with mitapivat and 71 (84%) treated with placebo; the most common events with mitapivat were headache, upper respiratory tract infection, initial insomnia, diarrhoea, and fatigue. Serious adverse events were reported in 19 (11%) patients treated with mitapivat and 13 (15%) treated with placebo. Ten (6%) patients who received mitapivat and one (1%) who received placebo discontinued study treatment due to adverse events. No deaths were reported. INTERPRETATION: Mitapivat significantly reduced the transfusion burden and was generally well tolerated, showing a favourable benefit-risk profile. These findings support mitapivat as the first oral disease-modifying therapy for adults with transfusion-dependent α-thalassaemia or β-thalassaemia, providing a new treatment option to reduce transfusion burden in this patient population. FUNDING: Agios Pharmaceuticals, Inc.
Adult↗