Forward-looking statements This document contains forward-looking statements. All statements other than statements of historical facts contained in this document, including statements regarding possible or assumed future

Wave Life Sciences Corporate

Presentation October 1, 2020 Exhibit 99.1

Forward-looking statements This

document contains forward-looking statements. All statements other than statements of historical facts contained in this document, including statements regarding possible or assumed future results of operations, preclinical and clinical studies,

business strategies, research and development plans, collaborations and partnerships, regulatory activities and timing thereof, competitive position, potential growth opportunities, use of proceeds and the effects of competition are forward-looking

statements. These statements involve known and unknown risks, uncertainties and other important factors that may cause the actual results, performance or achievements of Wave Life Sciences Ltd. (the "Company") to be materially different

from any future results, performance or achievements expressed or implied by the forward-looking statements. In some cases, you can identify forward-looking statements by terms such as "may," "will," "should,"

"expect," "plan," "aim," "anticipate," "could," "intend," "target," "project," "contemplate," "believe," "estimate,"

"predict," "potential" or "continue" or the negative of these terms or other similar expressions. The forward-looking statements in this presentation are only predictions. The Company has based these

forward-looking statements largely on its current expectations and projections about future events and financial trends that it believes may affect the Company's business, financial condition and results of operations. These forward-looking

statements speak only as of the date of this presentation and are subject to a number of risks, uncertainties and assumptions, including those listed under Risk Factors in the Company's Form 10-K and other filings with the SEC, some of which

cannot be predicted or quantified and some of which are beyond the Company's control. The events and circumstances reflected in the Company's forward-looking statements may not be achieved or occur, and actual results could differ

materially from those projected in the forward-looking statements. Moreover, the Company operates in a dynamic industry and economy. New risk factors and uncertainties may emerge from time to time, and it is not possible for management to predict

all risk factors and uncertainties that the Company may face. Except as required by applicable law, the Company does not plan to publicly update or revise any forward-looking statements contained herein, whether as a result of any new information,

future events, changed circumstances or otherwise.

Building a leading genetic medicines

company ALS: Amyotrophic lateral sclerosis; FTD: Frontotemporal dementia 1stereopure oligonucleotides and novel backbone chemistry modifications Innovative platform Stereopure oligonucleotides Novel backbone modifications (PN chemistry)

Allele-selectivity Multiple modalities (silencing, splicing, ADAR editing) Strong IP position1 Foundation of NEUROLOGY programs Huntington's disease ALS / FTD Ataxias Parkinson's disease Alzheimer's disease Clinical development

expertise Multiple global clinical trials ongoing across eight countries Innovative trial designs Manufacturing Established internal manufacturing capabilities to produce oligonucleotides at scale Wave's drug discovery and development

PRISM has unlocked novel and

proprietary advances in oligonucleotide design Backbone modifications Sugar modifications Drug approvals (FDA)2 1975 2020 2000 Mixtures of 2n molecules1 ~500,000 different molecules per dose fomivirsen pegaptanib Phosphorothioate (PS) mipomersen

nusinersen PN backbone modification chemistry Stereopure backbone 2'-4'-cEt 2'-O-methyl 2'-F 2'-4'-LNA 1n=number of chiral centers 2'-MOE Phosphorodiamidate Morpholino (PMO) eteplirsen golodirsen givosiran

patisiran inotersen viltolarsen 2oligonucleotide therapies approved by the FDA across the industry

THERAPEUTIC AREA / TARGET DISCOVERY

PRECLINICAL CLINICAL PARTNER Huntington's disease mHTT SNP1 Takeda 50:50 option Huntington's disease mHTT SNP2 Huntington's disease mHTT SNP3 ALS and FTD C9orf72 SCA3 ATXN3 CNS diseases Multiple Takeda milestones &

royalties ADAR editing Multiple 100% global ADAR editing Undisclosed 100% global Retinal diseases USH2A and RhoP23H 100% global NEUROLOGY HEPATIC OPTHALMOLOGY WVE-003 WVE-004 WVE-120101 WVE-120102 Innovative pipeline led by neurology programs

During a four-year term, Wave and Takeda may collaborate on up to six preclinical targets at any one time. ALS: Amyotrophic lateral sclerosis; FTD: Frontotemporal dementia; SCA3: Spinocerebellar ataxia 3 CNS: Central nervous system Stereopure

WVE-120101 WVE-120102 WVE-003

Huntington's Disease Portfolio

Huntington's disease: a

hereditary, fatal disorder Sources: Auerbach W, et al. Hum Mol Genet. 2001;10:2515-2523. Dragatsis I, et al. Nat Genet. 2000;26:300-306. Leavitt BR, et al. J Neurochem. 2006;96:1121-1129. Nasir J, et al. Cell. 1995;81:811-823. Reiner A, et al. J

Neurosci. 2001;21:7608-7619. White JK, et al. Nat Genet. 1997;17:404-410. Zeitlin S, et al. Nat Genet. 1995;11:155-163. Carroll JB, et al. Mol Ther. 2011;19:2178-2185. HDSA What is Huntington's disease?'

https://hdsa.org/what-is-hd/overview-of-huntingtons-disease/ Accessed: 11/2/18.; Becanovic, K., et al., Nat Neurosci, 2015. 18(6): p. 807-16. Van Raamsdonk, J.M., et al., Hum Mol Genet, 2005. 14(10): p. 1379-92.; Van Raamsdonk, J.M., et al., BMC

Neurosci, 2006. 7: p. 80. DNA CAG Repeat RNA wild-type (healthy) allele RNA mutant allele Normal CAG Repeat Expanded CAG Repeat Healthy protein (HTT) Mutant protein (mHTT) Neuro HD Autosomal dominant disease, characterized by cognitive decline,

psychiatric illness and chorea; fatal No approved disease-modifying therapies Expanded CAG triplet repeat in HTT gene results in production of mutant huntingtin protein (mHTT); accumulation of mHTT causes progressive loss of neurons in the brain

Wild-type (healthy) HTT protein critical for neuronal function; evidence suggests wild-type HTT loss of function plays a role in Huntington's disease 30,000 people with Huntington's disease in the US; another 200,000 at risk of

developing the condition

Evidence suggests wild-type or healthy

HTT is neuroprotective in an adult brain Transport of key neurotrophic factors such as brain-derived neurotrophic factor (BDNF) are regulated by wtHTT levels Relative proportion of wild-type to mutant protein is critical Increased amount of

wild-type protein relative to mutant HTT may result in slower disease progression (measured by age-at-onset) Patients with lack of wild-type have significantly more severe disease (measured by disease progression after symptom onset) Importance of

wild-type huntingtin (wtHTT) in HD Neuro HD Huntington's disease (HD) may be caused by a dominant gain of function in mutant HTT and a loss of function of wtHTT protein Sources: Van Raamsdonk, J.M., et al., Hum Mol Genet, 2005; Van Raamsdonk,

J.M., et al., BMC Neurosci, 2006; Becanovic, K., et al., Nat Neurosci, 2015; Saudou, F. and S. Humbert, The Biology of Huntingtin. Neuron, 2016; Gauthier, L.R., et al., Cell, 2004; Caviston, J.P. and E.L. Holzbaur, Trends Cell Biol, 2009; Ho, L.W.,

et al., J Med Genet, 2001, Zuccato et al., Science 2001; Zuccato et al., Brain Pathol 2007; Marullo et al. Genome Biol 2010; Squitieri et. al, Brain 2003 BDNF TrkB ERK CREB transport BDNF Neuroprotection

Nature publication contributes to

weight of evidence on importance of wild-type huntingtin Source: Poplawski et al., Nature, April 2019 Htt: Huntingtin protein Conditional knock-out of Htt in 4-month old mice (post-neuronal development) Results suggest that: Htt plays a central role

in the regenerating transcriptome (potentially influencing genes such as NFKB, STAT3, BDNF) Htt is essential for regeneration Indeed, conditional gene deletion showed that Htt is required for neuronal repair. Throughout life, neuronal maintenance

and repair are essential to support adequate cellular functioning Neuro HD

Increasing evidence on the

importance of wtHTT in HD pathogenesis, CNS and systemic health Striatum-specific defect in synaptic vesicle endocytosis that was not corrected by total lowering of HTT Corrected by overexpression of wild-type protein Striatal projection neurons

require HTT for motor regulation, synaptic development, cell health, and survival during aging Loss of HTT function could play a critical role in HD pathogenesis wtHTT in HD highlighted at CHDI 15th Annual HD Therapeutics Conference: HTT LOWERING:

EXPLORING DISTRIBUTION, TIMING, AND SAFETY (LOSS OF FUNCTION) Key points discussed at meeting: wtHTT has numerous critical functions throughout life (e.g., intracellular trafficking, cell-cell adhesion, BDNF transport) Near elimination of mouse

wtHtt detrimental regardless of when suppression begins Specific brain regions, e.g., STN, may be particularly vulnerable to wtHTT lowering Mouse Htt lowering can lead to thalamic, hepatic, pancreatic toxicity HTT LoF mutations highly constrained in

human population, suggesting selection against LoF mutations Recent publications on wtHTT LoF as a likely driver of HD pathogenesis LoF: Loss of function; wtHTT: wild-type huntingtin; HD: Huntington's disease; STN: subthalamic nucleus Neuro

Wild-type HTT in the cortex appears

critical for striatal health Presented by Dr. Frederic Saudou at Wave's Analyst and Investor Research Day on October 7, 2019 Virlogeux et al., Cell Reports 2018 Neuro HD Neuron Type Genetic Status Compartment Cortical Striatal Network Status

Functional Dysfunctional Post-synaptic Synaptic Presynaptic Status of the presynaptic compartment determines the integrity of the network

Utilize association between single

nucleotide polymorphisms (SNPs) and genetic mutations to specifically target errors in genetic disorders, including Huntington's disease (HD) Potential to provide treatment for up to 80% of HD population Wave approach: novel, allele-selective

silencing Source: Kay, et al. Personalized gene silencing therapeutics for Huntington disease. Clin Genet. 2014;86:29-36. Neuro HD Aims to lower mHTT transcript while leaving healthy wild-type HTT relatively intact Allele-selectivity possible

by targeting SNPs associated with expanded long CAG repeat in HTT gene RNase H and ASO:RNA RNA mutant allele

WVE-120101: Selective reduction of

mHTT mRNA and protein Reporter Cell Line* Neuro HD Source: Meena, Zboray L, Svrzikapa N, et al. Selectivity and biodistribution of WVE-120101, a potential antisense oligonucleotide therapy for the treatment of Huntington's disease. Paper

presented at: 69th Annual Meeting of the American Academy of Neurology; April 28, 2017; Boston, MA.

Demonstrated delivery to brain

tissue WVE-120101 and WVE-120102 distribution in cynomolgus non-human primate brain following intrathecal bolus injection In Situ Hybridization ViewRNA stained tissue Red dots are WVE-120102 oligonucleotide Arrow points to nuclear and perinuclear

distribution of WVE-120102 in caudate nucleus Red dots are WVE-120101 oligonucleotide Arrow points to nuclear and perinuclear distribution of WVE- 120101 in cingulate cortex CIC = cingulate cortex In Situ Hybridization ViewRNA stained tissue

Neuro HD CN = caudate nucleus Source: Meena, Zboray L, Svrzikapa N, et al. Selectivity and biodistribution of WVE-120101, a potential antisense oligonucleotide therapy for the treatment of Huntington's disease. Paper presented at: 69th Annual

Meeting of the American Academy of Neurology; April 28, 2017; Boston, MA.

Safety profile supported addition of

higher dose cohorts PRECISION-HD clinical trials Single Dose Multidose 196 1 Washout CSF sample Dose 28 56 84 112 Study Day* 140 OLE 2 mg 4 mg 8 mg 16 mg 32 mg PRECISION-HD2 and PRECISION-HD1 data, including 32 mg cohorts and OLE data, expected in

1Q 2021 Multidose Cohorts (N = 12 per cohort) PRECISION-HD2 interim data (2-16 mg cohorts pooled) OLE: Open label extension; CSF: cerebrospinal fluid; mHTT: mutant huntingtin; wtHTT: wild-type HTT; tHTT: total HTT * Study day may vary depending on

patient washout period 1Hodges-Lehmann non-parametric shift estimates of the difference between treatment and placebo, p<0.05 (Wilcoxon-Mann-Whitney non-parametric significance test); 3 2 Multiple Contrast Test (MCT), p=0.03; Interim data

announced December 2019 Biomarker Effects Two Phase 1b/2a clinical trials for WVE-120101 and WVE-120102 ongoing Patients are migrated to highest dose tested Reduction in mHTT (-12.4%1); Analysis across groups suggests dose response at highest

doses32 No change in total HTT Not all patients had reached Day 140 at interim analysis Neuro HD

Three allele-selective HD programs

Intend to explore efficacy in early manifest and pre-manifest HD patient populations Neuro HD Potential to address ~80% of HD patient population % Huntington's Disease Patient Population with SNP SNP1 WVE-120101 SNP2 WVE-120102 SNP3 WVE-003

SNP1 SNP2 SNP1 SNP2 SNP3 ~50% ~50% ~40% ~70%1 ~80%2 +10% of HD patients vs. SNP1 + SNP2 1 Percentage of patient population with SNP1 and/or SNP2 2 Percentage of patient population with SNP1, SNP2 and/or SNP3

WVE-003 (SNP3) approaching clinical

development Knockdown persists for 12 weeks in BACHD mouse model CTA: clinical trial application; wtHTT: wild-type huntingtin; mHTT: mutant huntingtin [Figure on right] Statistics: All oligo treatment groups statistically significantly different

from PBS; ***, P<0.005 Clinical development expected to initiate with CTA submission in 4Q 2020 Pan-silencing active comparator WVE-003 Relative HTT mRNA expression Log10 ( M compound concentration) Pan-silencing active comparator WVE-003

wtHTT mRNA Cortex Similar knockdown achieved in striatum Potent mutant HTT knockdown activity in homozygous iCell neurons No loss of selectivity with increasing concentrations mHTT mRNA Neuro HD Incorporates PN modified backbone chemistry

WVE-004 Amyotrophic Lateral

Sclerosis (ALS) Frontotemporal Dementia (FTD)

C9orf72 repeat expansions: A

critical genetic driver of ALS and FTD Normal (non-expanded) Allele < 25 GGGGCC repeats Expanded Allele Sources: DeJesus-Hernandez et al, Neuron, 2011. Renton et al, Neuron, 2011. Zhu et al, Nature Neuroscience, May 2020 Typically

100's-1000's of GGGGCC repeats C9orf72 hexanucleotide repeat expansions (GGGGCC) are the strongest known risk factor for sporadic and inherited forms of Amyotrophic Lateral Sclerosis (ALS) and Frontotemporal Dementia (FTD) The C9orf72

repeat expansions also lead to accumulation of repeat-containing transcripts, nuclear sequestration of RNA binding proteins and synthesis of toxic dipeptide-repeat (DPR) proteins The C9orf72 repeat expansions lead to reduced

expression of wild-type C9orf72 and to cellular changes that reduce neuronal viability Neuro C9orf72

C9-ALS and C9-FTD: Manifestations of

a clinical spectrum Disease C9 specific US population Mean disease duration Standard of care C9-ALS Fatal neurodegenerative disease Progressive degeneration of motor neurons in brain and spinal cord ~2,000 3.1 years Significant unmet need despite

two approved therapies C9-FTD Progressive neuronal atrophy in frontal/temporal cortices Personality and behavioral changes, gradual impairment of language skills ~10,000 6.4 years No approved disease modifying therapies Two devastating diseases with

a shared genetic basis ALS: Amyotrophic lateral sclerosis; FTD: Frontotemporal dementia Sources: Cammack et al, Neurology, October 2019. Moore et al, Lancet Neurology, February 2020 Neuro C9orf72

C9orf72 repeat expansions:

Mechanisms of cellular toxicity C9-ALS and C9-FTD may be caused by multiple factors: Insufficient levels of C9orf72 protein Accumulation of repeat-containing RNA transcripts Accumulation of aberrantly translated DPR proteins Recent evidence suggests

lowering C9orf72 protein exacerbates DPR-dependent toxicity Sources: Gitler et al, Brain Research, September 2016. Zhu et al, Nature Neuroscience, May 2020 Targeted by Wave ASOs Variant-selective targeting could address multiple potential drivers of

toxicity Neuro C9orf72

Normal C9orf72 allele produces three

mRNA transcripts (~80% are V2, ~20% are V1 and V3) Pathological allele with expanded repeat leads to healthy V2 and pathological V1 and V3 transcript by-products C9orf72 targeting strategy spares C9orf72 protein Wave C9orf72 candidate targets only

V1 and V3 transcripts, sparing V2 transcripts and healthy C9orf72 protein pre-mRNA variants Pathological mRNA products V1 V2 Mis-spliced V1/V3 Stabilized intron1 V3 Disease-causing factors RNA foci Dipeptide repeat proteins (DPRs) GGGGCC expansion

Accessible target for variant selectivity WVE-004 reduces Repeat-containing transcripts Neuro C9orf72