An ultra-rare progressive disease

What causes alpha-mannosidosis—and what is its long-term impact on patients?

A lysosomal storage disorder caused by α-mannosidase deficiency.^2,3

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Alpha-mannosidosis is a recessive disorder caused by gene variants in MAN2B1, which leads to a deficiency in α-mannosidase.³		Due to the reduced activity of α-mannosidase, mannose-rich oligosaccharides accumulate in lysosomes.^3,4		This leads to impaired cellular function throughout the body and a continuum of clinical manifestations.³

How rare is ultra-rare?

The incidence of alpha-mannosidosis is estimated at 1 in 500,000 to 1,000,000 live births.²

Incidence may be higher than previously thought. A genetic study of 1,010 individuals with a mucopolysaccharidosis (MPS)-like phenotype found a higher-than-expected number of alpha-mannosidosis cases.⁵

Clinical signs and symptoms associated with alpha-mannosidosis

Development at 20-30 years of age. Result of cerebral atrophy and cerebral demyelination.

Delayed development of speech. Delayed motor or mental function. IQ of 60-80 and a declining tendency over time.

Both conductive and sensorineural. Significantly affects 100% of patients over the age of 3 (hearing aids).

Infections are especially common in the first 10 years of life. Most common infections: upper airway, pulmonary, and acute/serous otitis media.

Leading to frequent infections (middle ear, gastrointestinal, and respiratory).

Affects 92% of adult patients and 62% of pediatric patients: joint contractures, scoliosis, genua valga, and hip dysplasia.

May develop in the first year of life.

Corneal clouding, cataract, partial blindness due to retinal pigmentary degeneration.

All patients show some degree of: short neck, large head with prominent forehead, rounded eyebrows, flattened nasal bridge, widely-spaced teeth, enlarged tongue.

Reduced dental quality, frequent cavities, tooth-grinding.

Cardiovascular system abnormalities in 24% of pediatric patients and 17% of adult patients.

In younger patients, a decrease in pulmonary function over time.

A factor in slow development of motor functions and uncoordinated movement.

Physical impairment revealed in the 6-minute walk and 3-minute stair-climbing tests, correlated with oligosaccharide level.

Alpha-mannosidosis is a progressive disease.
Early identification and timely treatment is critical.⁷

How to identify the broad range of symptoms that could signify alpha-mannosidosis^3,4,6

Know the symptoms—the most common symptoms of alpha-mannosidosis are^4,6:

Hearing impairment Speech delays Skeletal abnormalities Cognitive impairment

Know what to look for—the physical signs of alpha-mannosidosis are⁶:

Enlarged head Short neck Prominent brow ridge

Broad, flattened nose Prominent forehead Thick tongue

1.	Lamzede. Prescribing Information. Chiesi Farmaceutici S.p.A; 2023.
2.	Borgwardt L, Guffon N, Amraoui Y, et al. Efficacy and safety of Velmanase alfa in the treatment of patients with alpha-mannosidosis: results from the core and extension phase analysis of a phase III multicentre, double-blind, randomised, placebo-controlled trial. J Inherit Metab Dis. 2018;41(6):1215-1223. doi:10.1007/s10545-018-0185-0.
3.	Lund AM, Borgwardt L, Cattaneo F, et al. Comprehensive long-term efficacy and safety of recombinant human alpha-mannosidase (velmanase alfa) treatment in patients with alpha-mannosidosis. J Inherit Metab Dis. 2018;41(6):1225-1233. doi:10.1007/s10545-018-0175-2.
4.	Guffon N, Tylki-Szymanska A, Borgwardt L, et al. Recognition of alpha-mannosidosis in paediatric and adult patients: presentation of a diagnostic algorithm from an international working group. Mol Gen Metab. 2019;126(4):470-474. doi:10.1016/j.ymgme.2019.01.024.
5.	Borgwardt L, Stensland HMFR, Olsen KJ, et al. Alpha-mannosidosis: correlation between phenotype, genotype and mutant MAN2B1 subcellular localisation. Orphanet J Rare Dis. 2015;10:70. doi:10.1186/s13023-015-0286-x.
6.	Beck M, Olsen KJ, Wraith JE, et al. Natural history of alpha mannosidosis a longitudinal study. Orphanet J Rare Dis. 2013;8:88. doi:10.1186/1750-1172-8-88.
7.	Malm D, Nilssen Ø. Alpha-mannosidosis. Orphanet J Rare Dis. 2008;3:21. doi:10.1186/1750-1172-3-21.

1.	Lamzede. Prescribing Information. Chiesi Farmaceutici S.p.A; 2023.
2.	Borgwardt L, Lund AM, Dali CI. Alpha-mannosidosis—a review of genetic, clinical findings and options for treatment. Pediatr Endocrinol Rev. 2014;12(suppl1):185-191.
3.	Borgwardt L, Stensland HMFR, Olsen KJ, et al. Alpha-mannosidosis: correlation between phenotype, genotype and mutant MAN2B1 subcellular localisation. Orphanet J Rare Dis. 2015;10:70. doi:10.1186/s13023-015-0286-x.
4.	Beck M, Olsen KJ, Wraith JE, et al. Natural history of alpha mannosidosis a longitudinal study. Orphanet J Rare Dis. 2013;8:88. doi:10.1186/1750-1172-8-88.
5.	Wiesinger T, Schwarz M, Mechtler TP, et al. α-Mannosidosis—An underdiagnosed lysosomal storage disease in individuals with an ‘MPS-like’ phenotype. Mol Genet Metab. 2020;130(2):149-152. doi:10.1016/j.ymgme.2020.04.001
6.	Malm D, Nilssen Ø. Alpha-mannosidosis. Orphanet J Rare Dis. 2008;3:21. doi:10.1186/1750-1172-3-21.
7.	Guffon N, Tylki-Szymanska A, Borgwardt L, et al. Recognition of alpha-mannosidosis in paediatric and adult patients: presentation of a diagnostic algorithm from an international working group. Mol Gen Metab. 2019;126(4):470-474. doi:10.1016/j.ymgme.2019.01.024.

1.	Lamzede. Prescribing Information. Chiesi Farmaceutici S.p.A; 2023.
2.	Guffon N, Tylki-Szymanska A, Borgwardt L, et al. Recognition of alpha-mannosidosis in paediatric and adult patients: presentation of a diagnostic algorithm from an international working group. Mol Gen Metab. 2019;126(4):470-474. doi:10.1016/j.ymgme.2019.01.024.
3.	Wiesinger T, Schwarz M, Mechtler TP, et al. α-Mannosidosis—An underdiagnosed lysosomal storage disease in individuals with an ‘MPS-like’ phenotype. Mol Genet Metab. 2020;130(2):149-152. doi:10.1016/j.ymgme.2020.04.001
4.	Malm D, Nilssen Ø. Alpha-mannosidosis. Orphanet J Rare Dis. 2008;3:21. doi:10.1186/1750-1172-3-21.

1.	Lamzede. Prescribing Information. Chiesi Farmaceutici S.p.A; 2023.
2.	Borgwardt L, Lund AM, Dali CI. Alpha-mannosidosis – a review of genetic, clinical findings and options for treatment. Pediatr Endocrinol Rev. 2014;12(suppl1):185-191.
3.	The natural history of alpha-mannosidosis (HUE-MAN). ClinicalTrials.gov identifier: NCT00498420. Updated August 3, 2020. Accessed December 23, 2022. https://clinicaltrials.gov/ct2/show/NCT00498420.
4.	Safety study of recombinant human alpha-mannosidase for the treatment of patients with alpha-mannosidosis. ClinicalTrials.gov identifier: NCT01268358. Updated August 3, 2020. Accessed December 23, 2022. https://clinicaltrials.gov/ct2/show/NCT01268358.
5.	Dose finding study of recombinant human alpha-mannosidase for the treatment of patients with alpha-mannosidosis. ClinicalTrials.gov identifier: NCT01285700. Updated September 26, 2012. Accessed December 23, 2022. https://clinicaltrials.gov/ct2/show/NCT01285700.
6.	Long-term efficacy and safety of lamazym for the treatment of patients with alpha-mannosidosis. ClinicalTrials.gov identifier: NCT01681940. Updated March 29, 2017. Accessed December 23, 2022. https://clinicaltrials.gov/ct2/show/NCT01681940.
7.	Trial on safety and efficacy of velmanase alfa treatment in pediatric patients with alpha-mannosidosis (rhLaman-08). ClinicalTrials.gov identifier: NCT02998879. Updated October 26, 2021. Accessed December 23, 2022. https://clinicaltrials.gov/ct2/show/NCT02998879.
8.	A placebo-controlled phase 3 trial of repeated lamazym treatment of subjects with alpha-mannosidosis. ClinicalTrials.gov identifier: NCT01681953. Updated August 3, 2020. Accessed December 23, 2022. https://clinicaltrials.gov/ct2/show/NCT01681953.
9.	Borgwardt L, Guffon N, Amraoui Y, et al. Efficacy and safety of Velmanase alfa in the treatment of patients with alpha-mannosidosis: results from the core and extension phase analysis of a phase III multicentre, double-blind, randomised, placebo-controlled trial. J Inherit Metab Dis. 2018;41(6):1215-1223. doi: 10.1007/s10545-018-0185-0.
10.	Lund AM, Borgwardt L, Cattaneo F, et al. Comprehensive long-term efficacy and safety of recombinant human alpha-mannosidase (velmanase alfa) treatment in patients with alpha-mannosidosis. J Inherit Metab Dis. 2018;41(6):1225-1233. doi:10.1007/s10545-018-0175-2.
11.	Evaluation of long-term efficacy of treatment with lamazym (rhLAMAN-10). ClinicalTrials.gov identifier: NCT02478840. Updated November 20, 2020. Accessed December 23, 2022. https://clinicaltrials.gov/ct2/show/NCT02478840.

An ultra-rare progressive disease

What causes alpha-mannosidosis—and what is its long-term impact on patients?

How rare is ultra-rare?

The incidence of alpha-mannosidosis is estimated at 1 in 500,000 to 1,000,000 live births.2

Clinical signs and symptoms associated with alpha-mannosidosis

How to identify the broad range of symptoms that could signify alpha-mannosidosis3,4,6

The incidence of alpha-mannosidosis is estimated at 1 in 500,000 to 1,000,000 live births.²

How to identify the broad range of symptoms that could signify alpha-mannosidosis^3,4,6