RARE DISEASE
Pyruvate dehydrogenase deficiency
Pyruvate dehydrogenase deficiency
Pyruvate dehydrogenase deficiency
Synonyms: PDH, PDHC, Pyruvate dehydrogenase complex deficiency
Synonyms: PDH, PDHC, Pyruvate dehydrogenase complex deficiency
Synonyms: PDH, PDHC, Pyruvate dehydrogenase complex deficiency
Drug discovery
1
drug
With orphan designation
Overview
Pyruvate dehydrogenase deficiency (PDHD) is a rare X-linked or autosomal recessive mitochondrial disorder caused by mutations in genes encoding components of the pyruvate dehydrogenase complex (PDC), most commonly PDHA1 (75-80% of cases) [1][6][15]. It disrupts carbohydrate metabolism, leading to lactic acidosis and progressive neurological impairments such as developmental delay, hypotonia, seizures, and structural brain anomalies (e.g., corpus callosum hypoplasia, Leigh syndrome) [1][2][6]. Onset ranges from severe neonatal forms with high mortality to later-onset cases with episodic symptoms. Diagnosis involves elevated blood/CSF lactate, genetic testing, and neuroimaging [6][9][15].
Burden
High mortality (43% die before age 3 months; 91% by age 4) [4][5], with survivors requiring lifelong multidisciplinary care.
Neurological morbidity (e.g., severe intellectual disability, cortical blindness) and recurrent hospitalizations contribute to significant financial/emotional strain [1][15][19].
Structural brain anomalies (e.g., ventriculomegaly) in >85% of patients necessitate early neurodevelopmental interventions [2][6][15].
Therapies
Ketogenic diet: First-line therapy to bypass impaired glycolysis, though limited impact on neurological damage [3][6][15].
Dichloroacetate: Reduces lactic acidosis; phase 3 trials for FDA-approved formulation (SL1009) ongoing [3][8][15].
Adjunctive therapies: Thiamine (responsive in specific mutations), phenylbutyrate (for select PDHA1 variants), and supportive care (seizure/acidosis management) [3][6][12][16].
Categories: rare genetic diseases, rare inborn errors of metabolism, rare neurological diseases
Research Papers
334 drug discovery papers about Pyruvate dehydrogenase deficiency, with 1 first-in-class and 3 next-in-class emerging drug candidates forecasted to outperform the average preclinical success rate. Recent publications:
334 drug discovery papers about Pyruvate dehydrogenase deficiency, with 1 first-in-class and 3 next-in-class emerging drug candidates forecasted to outperform the average preclinical success rate. Recent publications:
2026-08-06 | Neurological, Neurodevelopmental and Treatment Outcomes in Patients With Pyruvate Dehydrogenase Complex Deficiency.
The aim of this study was to characterize intellectual and motor function, neurological features including epilepsy, treatment response, and adaptive behavior in patients with pyruvate dehydrogenase complex deficiency (PDCD) in Sweden. Forty-two individuals with genetically confirmed PDCD (86% PDHA1-related disease) were identified from a nationwide epidemiological study and were included in this cross-sectional study comprising systematic neurological evaluations (n = 41) and caregiver interviews assessing adaptive behavior (n = 35). Intellectual disability was detected in 33/42 (79%) individuals, while 31/35 (89%) demonstrated significant impairments in adaptive functioning. Although 27/39 (69%) were ambulatory, only 8/39 (21%) demonstrated age-appropriate walking ability. Clinical signs of polyneuropathy were observed in 24/41 (59%), bulbar symptoms in 22/41 (54%), spasticity in 19/41 (46%), ataxia in 13/41 (32%), and dystonia in 9/41 (22%). Lifetime epilepsy was present in 16/41 (39%) of individuals. Ketogenic diet treatment, administered to 30 individuals, was effective in both prenatal- and postnatal-onset disease. Seizure frequency decreased in individuals with epilepsy (8/9; 89%) and relapses of dystonia, ataxia, exercise intolerance, and lactic acidosis were prevented in all affected individuals (15/15). Improvements in communication and motor function were also noted. Intellectual disability and deficits in adaptive behavior are frequent in PDCD, although cognitive outcomes are more heterogeneous among individuals with postnatal onset. Prenatal onset and epilepsy are associated with severe-profound intellectual disability. Although most are ambulatory, motor deficits are frequent. A ketogenic diet treatment is a safe and effective therapeutic option, contributing to both seizure control and remission of neurological deterioration relapses.
2026-07-10 | Dichloroacetate improves animal survival, growth, neuromuscular activity, mitochondrial stress and physiology, and elevated lactate in C. elegans pdha-1 and dld-1 RNAi models of pyruvate dehydrogenase complex deficiency (PDCD)
Pyruvate dehydrogenase complex (PDHc) deficiency (PDCD) is a primary mitochondrial disorder characterized by neurodevelopmental disability, altered intermediary metabolism and early mortality. Dichloroacetate (DCA), a pyruvate analogue, is a well-described PDHc activator that remains under clinical investigation for treatment of PDCD. Here, we studied the in vivo efficacy of a 5-point log concentration range of DCA on animal health and metabolism in C. elegans with feeding RNA interference (RNAi) expression knockdown of either PDHA-1 or DLD-1 homologues at graded degrees to model variable disease severity. These worm models recapitulate phenotypic features of PDCD observed in human patients, including reduced survival, delayed growth, locomotor impairment, and elevated lactate and/or pyruvate tissue levels. DCA treatment appeared well-tolerated, with no gross morphologic toxicity seen at doses up to 25 mM. Significantly improved health, survival, tissue lactate levels, and mitochondrial physiology were observed at 25 mM in pdha-1(RNAi) knockdown animals. DCA treatment in dld-1(RNAi) C. elegans models (undiluted, 1:20 dilution, and 1:100 dilution) showed significant therapeutic benefits on survival, neuromuscular function and metabolic phenotypes primarily in the moderate (1:20) and/or mild (1:100) dld-1(RNAi) deficiency strains, but not in full-dose dld-1(RNAi). Importantly, linear growth, neuromuscular activity, and mitochondrial physiology were significantly improved with DCA treatment even in the most severe dld-1(RNAi) undiluted model. Overall, preclinical modeling provides objective evidence of DCA therapeutic efficacy in C. elegans expression knockdown strains for two well-conserved homologues of PDHA1 and DLD that represent distinct genetic etiologies of PDHc deficiency, with demonstrated beneficial effects on survival, healthspan, tissue lactate, and mitochondrial physiology. These data further confirm that DCA's therapeutic effect correlates with PDHc disease phenotype severity in dld-1(RNAi) animals.
2026-06-25 | Ketogenic diet therapy in pyruvate dehydrogenase deficiency: Global clinical practice from literature and survey data.
Pyruvate dehydrogenase deficiency (PDHD) is a rare mitochondrial disorder characterized by impaired carbohydrate metabolism, resulting in lactic acidosis and neurological dysfunction. Ketogenic diet therapy (KDT) is commonly used to bypass defective glucose metabolism; however, evidence guiding clinical practice remains limited. To evaluate global clinical practice and published evidence regarding the use of KDT in children and young people with PDHD. A combined literature review and international clinician survey were conducted. A systematic search identified studies reporting KDT use in PDHD. Two international surveys targeting registered dietitians and medical doctors collected data on clinical practice, diet initiation, monitoring, outcomes, and adverse effects. Forty studies describing 129 patients were identified, predominantly case reports or series. Survey responses were obtained from 41 dietitians (142 patients) and 14 physicians (64 patients) across multiple regions. All physician respondents supported referral for KDT at diagnosis regardless of genotype. Classical ketogenic diets were most commonly prescribed, though modified approaches were frequently used in clinical practice to improve feasibility and palatability. Target β-hydroxybutyrate levels typically ranged between 2 and 4 mmol/L, although treatment was frequently individualized. Findings demonstrated improvements in seizure control, motor function, cognition, and quality of life. Adverse effects were primarily gastrointestinal. KDT is a widely used and generally well tolerated therapeutic strategy for PDHD across genotypes and age groups, with reported clinical benefits extending beyond seizure control. Clinical practice demonstrates variability, reflecting the limited high-quality evidence base. Development of standardized but flexible clinical guidelines and further longitudinal studies are needed to optimize patient outcomes.
2026-06-05 | The Metabolic Nexus of Indigenous Health Disparities: Exploring the Intersecting Roles of Enterotoxigenic Bacteroides fragilis (ETBF), Thiamine, and Niacin
Title The Metabolic Nexus of Indigenous Health Disparities: Exploring the Intersecting Roles of Enterotoxigenic Bacteroides fragilis (ETBF), Thiamine, and Niacin Description / Abstract This position paper outlines a novel, unified biochemical paradigm to explain the persistent disparities in acute and chronic disease burdens between First Nations populations and non-Indigenous demographics in Canada. Rather than analyzing metabolic syndromes, vascular illnesses, and severe infectious outcomes through isolated clinical lenses, this paper introduces a compounding, lethal molecular cycle driven by Enterotoxigenic Bacteroides fragilis (ETBF)—the leading anaerobic cause of septicemia and bacteremia in human medicine. The research details how ETBF acts as a metabolic hijacker within the host gastrointestinal tract. By utilizing its signature toxin (BFT) to cleave E-cadherin and destroy epithelial tight junctions, the pathobiont downregulates host thiamine (Vitamin B1) and niacin (Vitamin B3) transport machinery, inducing localized malabsorption. This targeted depletion paralyzes the mitochondrial gateway enzyme, Pyruvate Dehydrogenase (PDH), forcing healthy tissue into an inefficient, anaerobic "Warburg effect." The resulting lactic acidosis creates an acidic, hypoxic microenvironment that suppresses host T-cell and macrophage responses, allowing the highly drug-resistant pathobiont to multiply unchecked and escape into the bloodstream. Furthermore, this paper highlights a critical pharmacological paradox: standard chronic care interventions, specifically the widespread use of metformin for Type 2 diabetes, act as competitive inhibitors of the human Thiamine Transporter-2 (hTHTR-2) receptor. This drug-nutrient interaction, combined with accelerated diabetic renal washout and the biological "weathering" effects of intergenerational trauma, leaves vulnerable hosts in a state of profound, hidden mitochondrial thiamine depletion. When an infection occurs, standard empirical antibiotic monotherapy frequently fails because it does not address the underlying cellular energy crisis. Ultimately, this paper argues for a clinical shift toward metabolic resuscitation. By analyzing the genetic feedback networks of ETBF—specifically its reliance on cis-acting TPP riboswitches—the paper details how the strategic co-administration of high-dose intravenous thiamine alongside broad-spectrum antibiotics can neutralize the pathogen's competitive edge, re-activate human mitochondrial respiration, and clear lethal lactic acidosis. This framework offers an actionable, molecular pathway toward dismantling deep-seated health inequities and restoring metabolic harmony in First Nations communities. Keywords First Nations Health; Indigenous Health Disparities; Enterotoxigenic Bacteroides fragilis (ETBF); Thiamine Deficiency (Vitamin B1); Niacin (Vitamin B3); Sepsis / Septicemia; Metformin Drug-Nutrient Interaction; Warburg Effect; TPP Riboswitch; Metabolic Resuscitation; Intergenerational Trauma; Allostatic Load.
2026-04-21 | Benefits and adverse effects of ketogenic diet treatment in pediatric patients with inborn errors of metabolism.
The ketogenic diet (KD) is an established therapeutic option for epilepsy and selected inborn errors of metabolism (IEMs), particularly glucose transporter type 1 deficiency (GLUT1D) and pyruvate dehydrogenase complex deficiency (PDCD). Increasing evidence suggests broader applications of KD in pediatric metabolic disorders; however, data on its safety and efficacy in heterogeneous IEM populations remain limited. To evaluate the efficacy, clinical benefits, and adverse effects (AEs) of KD in pediatric patients with various IEMs. A retrospective analysis was conducted in pediatric patients with IEMs receiving KD treatment. Patients were categorized into 3 groups: 1) other IEMs (n = 7), 2) mitochondrial diseases (MD) (n = 17), and 3) GLUT1D and PDCD (n = 20). The median age at initiation of KD was 37, 53, and 53 months, respectively, and the median duration of KD treatment was 5, 11, and 55 months in groups 1, 2, and 3. The KD was associated with clinical benefits in 84% of patients. Among children with epilepsy (n = 23), a seizure reduction of >50% was observed in 73.9% of patients, including complete seizure freedom in 4 individuals. Improvements were also noted in muscle tone (27.6%), exercise tolerance (51.2%), ataxia (83.3%), and involuntary movements (60%). Lactate levels decreased in 84.6% of patients with mitochondrial disease and in all patients with PDCD. The KD was discontinued in 12 patients due to insufficient efficacy (n = 5) or AEs (AEs; n = 7). The most common AEs included gastrointestinal (GI) symptoms, dyslipidemia, hyperuricemia, metabolic acidosis, and decreased free carnitine; most were transient. No significant association was found between median β-hydroxybutyrate (BHB) levels and clinical outcomes. The KD is an effective and generally well-tolerated therapeutic option in pediatric IEMs, with benefits extending beyond seizure control. Adverse effects are typically manageable, although GI intolerance may limit long-term use. Ketogenic diet should be considered not only for refractory epilepsy but also for selected metabolic indications.
2026-08-06 | Neurological, Neurodevelopmental and Treatment Outcomes in Patients With Pyruvate Dehydrogenase Complex Deficiency.
The aim of this study was to characterize intellectual and motor function, neurological features including epilepsy, treatment response, and adaptive behavior in patients with pyruvate dehydrogenase complex deficiency (PDCD) in Sweden. Forty-two individuals with genetically confirmed PDCD (86% PDHA1-related disease) were identified from a nationwide epidemiological study and were included in this cross-sectional study comprising systematic neurological evaluations (n = 41) and caregiver interviews assessing adaptive behavior (n = 35). Intellectual disability was detected in 33/42 (79%) individuals, while 31/35 (89%) demonstrated significant impairments in adaptive functioning. Although 27/39 (69%) were ambulatory, only 8/39 (21%) demonstrated age-appropriate walking ability. Clinical signs of polyneuropathy were observed in 24/41 (59%), bulbar symptoms in 22/41 (54%), spasticity in 19/41 (46%), ataxia in 13/41 (32%), and dystonia in 9/41 (22%). Lifetime epilepsy was present in 16/41 (39%) of individuals. Ketogenic diet treatment, administered to 30 individuals, was effective in both prenatal- and postnatal-onset disease. Seizure frequency decreased in individuals with epilepsy (8/9; 89%) and relapses of dystonia, ataxia, exercise intolerance, and lactic acidosis were prevented in all affected individuals (15/15). Improvements in communication and motor function were also noted. Intellectual disability and deficits in adaptive behavior are frequent in PDCD, although cognitive outcomes are more heterogeneous among individuals with postnatal onset. Prenatal onset and epilepsy are associated with severe-profound intellectual disability. Although most are ambulatory, motor deficits are frequent. A ketogenic diet treatment is a safe and effective therapeutic option, contributing to both seizure control and remission of neurological deterioration relapses.
2026-07-10 | Dichloroacetate improves animal survival, growth, neuromuscular activity, mitochondrial stress and physiology, and elevated lactate in C. elegans pdha-1 and dld-1 RNAi models of pyruvate dehydrogenase complex deficiency (PDCD)
Pyruvate dehydrogenase complex (PDHc) deficiency (PDCD) is a primary mitochondrial disorder characterized by neurodevelopmental disability, altered intermediary metabolism and early mortality. Dichloroacetate (DCA), a pyruvate analogue, is a well-described PDHc activator that remains under clinical investigation for treatment of PDCD. Here, we studied the in vivo efficacy of a 5-point log concentration range of DCA on animal health and metabolism in C. elegans with feeding RNA interference (RNAi) expression knockdown of either PDHA-1 or DLD-1 homologues at graded degrees to model variable disease severity. These worm models recapitulate phenotypic features of PDCD observed in human patients, including reduced survival, delayed growth, locomotor impairment, and elevated lactate and/or pyruvate tissue levels. DCA treatment appeared well-tolerated, with no gross morphologic toxicity seen at doses up to 25 mM. Significantly improved health, survival, tissue lactate levels, and mitochondrial physiology were observed at 25 mM in pdha-1(RNAi) knockdown animals. DCA treatment in dld-1(RNAi) C. elegans models (undiluted, 1:20 dilution, and 1:100 dilution) showed significant therapeutic benefits on survival, neuromuscular function and metabolic phenotypes primarily in the moderate (1:20) and/or mild (1:100) dld-1(RNAi) deficiency strains, but not in full-dose dld-1(RNAi). Importantly, linear growth, neuromuscular activity, and mitochondrial physiology were significantly improved with DCA treatment even in the most severe dld-1(RNAi) undiluted model. Overall, preclinical modeling provides objective evidence of DCA therapeutic efficacy in C. elegans expression knockdown strains for two well-conserved homologues of PDHA1 and DLD that represent distinct genetic etiologies of PDHc deficiency, with demonstrated beneficial effects on survival, healthspan, tissue lactate, and mitochondrial physiology. These data further confirm that DCA's therapeutic effect correlates with PDHc disease phenotype severity in dld-1(RNAi) animals.
2026-06-25 | Ketogenic diet therapy in pyruvate dehydrogenase deficiency: Global clinical practice from literature and survey data.
Pyruvate dehydrogenase deficiency (PDHD) is a rare mitochondrial disorder characterized by impaired carbohydrate metabolism, resulting in lactic acidosis and neurological dysfunction. Ketogenic diet therapy (KDT) is commonly used to bypass defective glucose metabolism; however, evidence guiding clinical practice remains limited. To evaluate global clinical practice and published evidence regarding the use of KDT in children and young people with PDHD. A combined literature review and international clinician survey were conducted. A systematic search identified studies reporting KDT use in PDHD. Two international surveys targeting registered dietitians and medical doctors collected data on clinical practice, diet initiation, monitoring, outcomes, and adverse effects. Forty studies describing 129 patients were identified, predominantly case reports or series. Survey responses were obtained from 41 dietitians (142 patients) and 14 physicians (64 patients) across multiple regions. All physician respondents supported referral for KDT at diagnosis regardless of genotype. Classical ketogenic diets were most commonly prescribed, though modified approaches were frequently used in clinical practice to improve feasibility and palatability. Target β-hydroxybutyrate levels typically ranged between 2 and 4 mmol/L, although treatment was frequently individualized. Findings demonstrated improvements in seizure control, motor function, cognition, and quality of life. Adverse effects were primarily gastrointestinal. KDT is a widely used and generally well tolerated therapeutic strategy for PDHD across genotypes and age groups, with reported clinical benefits extending beyond seizure control. Clinical practice demonstrates variability, reflecting the limited high-quality evidence base. Development of standardized but flexible clinical guidelines and further longitudinal studies are needed to optimize patient outcomes.
2026-06-05 | The Metabolic Nexus of Indigenous Health Disparities: Exploring the Intersecting Roles of Enterotoxigenic Bacteroides fragilis (ETBF), Thiamine, and Niacin
Title The Metabolic Nexus of Indigenous Health Disparities: Exploring the Intersecting Roles of Enterotoxigenic Bacteroides fragilis (ETBF), Thiamine, and Niacin Description / Abstract This position paper outlines a novel, unified biochemical paradigm to explain the persistent disparities in acute and chronic disease burdens between First Nations populations and non-Indigenous demographics in Canada. Rather than analyzing metabolic syndromes, vascular illnesses, and severe infectious outcomes through isolated clinical lenses, this paper introduces a compounding, lethal molecular cycle driven by Enterotoxigenic Bacteroides fragilis (ETBF)—the leading anaerobic cause of septicemia and bacteremia in human medicine. The research details how ETBF acts as a metabolic hijacker within the host gastrointestinal tract. By utilizing its signature toxin (BFT) to cleave E-cadherin and destroy epithelial tight junctions, the pathobiont downregulates host thiamine (Vitamin B1) and niacin (Vitamin B3) transport machinery, inducing localized malabsorption. This targeted depletion paralyzes the mitochondrial gateway enzyme, Pyruvate Dehydrogenase (PDH), forcing healthy tissue into an inefficient, anaerobic "Warburg effect." The resulting lactic acidosis creates an acidic, hypoxic microenvironment that suppresses host T-cell and macrophage responses, allowing the highly drug-resistant pathobiont to multiply unchecked and escape into the bloodstream. Furthermore, this paper highlights a critical pharmacological paradox: standard chronic care interventions, specifically the widespread use of metformin for Type 2 diabetes, act as competitive inhibitors of the human Thiamine Transporter-2 (hTHTR-2) receptor. This drug-nutrient interaction, combined with accelerated diabetic renal washout and the biological "weathering" effects of intergenerational trauma, leaves vulnerable hosts in a state of profound, hidden mitochondrial thiamine depletion. When an infection occurs, standard empirical antibiotic monotherapy frequently fails because it does not address the underlying cellular energy crisis. Ultimately, this paper argues for a clinical shift toward metabolic resuscitation. By analyzing the genetic feedback networks of ETBF—specifically its reliance on cis-acting TPP riboswitches—the paper details how the strategic co-administration of high-dose intravenous thiamine alongside broad-spectrum antibiotics can neutralize the pathogen's competitive edge, re-activate human mitochondrial respiration, and clear lethal lactic acidosis. This framework offers an actionable, molecular pathway toward dismantling deep-seated health inequities and restoring metabolic harmony in First Nations communities. Keywords First Nations Health; Indigenous Health Disparities; Enterotoxigenic Bacteroides fragilis (ETBF); Thiamine Deficiency (Vitamin B1); Niacin (Vitamin B3); Sepsis / Septicemia; Metformin Drug-Nutrient Interaction; Warburg Effect; TPP Riboswitch; Metabolic Resuscitation; Intergenerational Trauma; Allostatic Load.
2026-04-21 | Benefits and adverse effects of ketogenic diet treatment in pediatric patients with inborn errors of metabolism.
The ketogenic diet (KD) is an established therapeutic option for epilepsy and selected inborn errors of metabolism (IEMs), particularly glucose transporter type 1 deficiency (GLUT1D) and pyruvate dehydrogenase complex deficiency (PDCD). Increasing evidence suggests broader applications of KD in pediatric metabolic disorders; however, data on its safety and efficacy in heterogeneous IEM populations remain limited. To evaluate the efficacy, clinical benefits, and adverse effects (AEs) of KD in pediatric patients with various IEMs. A retrospective analysis was conducted in pediatric patients with IEMs receiving KD treatment. Patients were categorized into 3 groups: 1) other IEMs (n = 7), 2) mitochondrial diseases (MD) (n = 17), and 3) GLUT1D and PDCD (n = 20). The median age at initiation of KD was 37, 53, and 53 months, respectively, and the median duration of KD treatment was 5, 11, and 55 months in groups 1, 2, and 3. The KD was associated with clinical benefits in 84% of patients. Among children with epilepsy (n = 23), a seizure reduction of >50% was observed in 73.9% of patients, including complete seizure freedom in 4 individuals. Improvements were also noted in muscle tone (27.6%), exercise tolerance (51.2%), ataxia (83.3%), and involuntary movements (60%). Lactate levels decreased in 84.6% of patients with mitochondrial disease and in all patients with PDCD. The KD was discontinued in 12 patients due to insufficient efficacy (n = 5) or AEs (AEs; n = 7). The most common AEs included gastrointestinal (GI) symptoms, dyslipidemia, hyperuricemia, metabolic acidosis, and decreased free carnitine; most were transient. No significant association was found between median β-hydroxybutyrate (BHB) levels and clinical outcomes. The KD is an effective and generally well-tolerated therapeutic option in pediatric IEMs, with benefits extending beyond seizure control. Adverse effects are typically manageable, although GI intolerance may limit long-term use. Ketogenic diet should be considered not only for refractory epilepsy but also for selected metabolic indications.
Access all drug discovery papers and probability of success in trials forecasts:
Access all drug discovery papers and probability of success in trials forecasts:
Drug Discovery Landscape
1 orphan drug designation for Pyruvate dehydrogenase deficiency.
1 orphan drug designation for Pyruvate dehydrogenase deficiency.
Drug | Therapy type | Regulator | Orphan designation | Approval | Sponsor |
|---|---|---|---|---|---|
Sodium phenylbutyrate | small molecules | EMA | 2015-11-11 | — | Fondazione Telethon Ets |
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