Drug discovery
14
drugs
With orphan designations
Overview
GM2 gangliosidosis is a group of autosomal recessive lysosomal storage disorders caused by deficiencies in β-hexosaminidase enzymes (A, B, or GM2 activator protein), leading to toxic GM2 ganglioside accumulation in neurons. Subtypes include Tay-Sachs (HEXA mutations), Sandhoff (HEXB mutations), and AB-variant (GM2A mutations) diseases. Infantile forms cause rapid neurodegeneration, developmental regression, and death by age 4–5, while juvenile/adult-onset variants show slower progression with motor neuron dysfunction, cerebellar atrophy, and psychiatric manifestations [1][2][5][7]. No disease-modifying therapies are currently approved [3][5].
Population
Incidence ranges from 1:222,000 (Tay-Sachs) to 1:422,000 (Sandhoff) live births, with higher carrier rates in Ashkenazi Jewish, Cajun, and French Canadian populations [2][9].
Adult-onset cases (average age 19) account for 6–7% of GM2 gangliosidoses, presenting with proximal weakness (81%), cerebellar ataxia (53%), and psychiatric disorders (30%) [1][4].
Burden
Infantile/juvenile forms: 93% require wheelchair assistance within 20 years of onset; 85% develop seizures, and 100% lose speech [2][4][11].
Adult forms: 44% develop fractures, 41% experience falls, and 30% require psychiatric care [4][11].
Caregiver impact: 100% report pervasive daily care responsibilities, with 69% managing behavioral/psychiatric crises and 45% experiencing severe emotional strain [11][14].
Therapies
Experimental approaches: Gene therapy (AAV vectors, CRISPR/Cas9), enzyme replacement therapy (intrathecal/cerebroventricular delivery), and hematopoietic stem cell transplantation (limited CNS efficacy) [5][13][17].
Symptomatic management: Gastric tube placement prolongs survival in infantile cases; anticonvulsants and mobility aids address neurological deficits [2][4][11].
Failed strategies: Substrate reduction therapy (miglustat) showed no clinical benefit in trials [8][17].
Categories: rare genetic diseases, rare inborn errors of metabolism, rare neurological diseases, rare transplant-related disorders
Drug Discovery Landscape
Drug | Therapy type | Regulator | Orphan designation | Approval | Sponsor |
|---|---|---|---|---|---|
(2S,3R,4R,5S)-1-[5-(2-fluoro-biphenyl-4-ylmethoxy)-pentyl]-2-hydroxymethyl-piperidine-3,4,5-triol | small molecules | EMA | 2023-02-15 | — | Azafaros B.V. |
N-acetyl-L-leucine | small molecules | FDA | 2022-01-11 | — | IntraBio Inc. |
Gemfibrozil | small molecules | FDA | 2021-08-27 | — | Polaryx Therapeutics, Inc. |
Adeno-associated viral vector serotype 9 containing the human HEXA and HEXB genes | gene therapies | EMA | 2021-08-20 | — | Raremoon Consulting Esp S.L. |
Trans-Cinnamic Acid | small molecules | FDA | 2020-11-24 | — | Polaryx Therapeutics, Inc. |
Venglustat | small molecules | EMA | 2020-08-21 | — | Sanofi B.V. |
venglustat malate | small molecules | FDA | 2020-08-13 | — | Genzyme Corporation, a SANOFI COMPANY |
adeno-associated viral vector serotype 9 (AAV9) carrying both HEXA and HEXB | gene therapies | FDA | 2020-07-17 | — | Taysha Gene Therapies |
(2S,3R,4R,5S)-2-(hydroxymethyl)-1-pentylpiperidine-3,4,5-triol | small molecules | EMA | 2019-11-13 | — | Idorsia Pharmaceuticals Deutschland GmbH |
sinbaglustat | small molecules | FDA | 2019-08-01 | — | Idorsia Pharmaceuticals Ltd |
N-acetyl-DL-leucine | small molecules | FDA | 2018-03-26 | — | IntraBio Inc. |
Recombinant adeno-associated viral vector serotype 2/1 encoding human beta-hexosaminidase alpha and beta subunits | gene therapies | EMA | 2018-01-17 | — | Maria Livadiotis |
Acetylleucine | peptides | EMA | 2017-12-12 | — | IntraBio Ireland Ltd |
Recombinant adeno-associated virus serotype 2/1 vector encoding human beta-hexosaminidase alpha & beta subunits (rAAV2/1 Hex alpha & beta) | gene therapies | FDA | 2017-11-14 | — | University of Cambridge |