Acknowledgements & Disclosures All Wave Life Sciences employees Prof. Gregory Verdine, co-founder & Director Wave Life Sciences Prof. Takeshi Wada, co-founder Wave Life Sciences Prof. Matthew Wood, Department of Physiolo

Stereochemical Control of Antisense

Oligonucleotides Enhances Target Efficacy Chandra Vargeese, PhD SVP, Drug Discovery Wave Life Sciences October 3, 2018 Exhibit 99.1

Acknowledgements & Disclosures All

Wave Life Sciences employees Prof. Gregory Verdine, co-founder & Director Wave Life Sciences Prof. Takeshi Wada, co-founder Wave Life Sciences Prof. Matthew Wood, Department of Physiology, Anatomy and Genetics, University of Oxford Chandra

Vargeese is an employee of Wave Life Sciences

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.

Architects of transformation Wave Life

Sciences is a clinical-stage, genetic medicines company unlocking the potential of a proprietary chemistry platform that enables the precise design, optimization and production of stereopure nucleic acid therapies. Wave has reinvented the design,

synthesis and manufacture of nucleic acid therapies to potentially optimize potency, durability and safety PRECISION Ability to design nucleic acid compounds that have one defined and consistent profile SCALE Platform potential across multiple

modalities and tissues Internal expertise and capacity for large-scale GMP manufacturing Wave's chemistry platform is built on a foundation of two core capabilities

History of oligonucleotide therapeutics

Backbone modifications Introduce chiral centers Generate mixtures Sugar modifications Drug approvals (FDA) Chiral Phosphorothioate Chiral Phosphorodiamidite Morpholino (PMO) Mixtures of 2n molecules (n=No. of chiral centers) SEQUENCE

STEREOCHEMISTRY CHEMISTRY Fomiversen Pegaptanib Mipomerse Eteplirsen Nusinersen Patisiran Stereopure ASOs enter clinic Wave Stereopure ASOs Oka N, Wada T, Saigo K. JACS. 2002 Stec WJ, et al. J Am Chem Soc. 1989 ~500,000 different molecules per

Advances in stereopure oligonucleotide

synthesis and manufacturing Versatility in Chemistry Versatility in Scale High Crude Purity Improved synthetic capabilities Custom building blocks - Tunable R' groups - Various 2'-modifications

Candidate Optimization and Selection GMP Quality High-throughput scale Manufacturing scale

Wave's chemistry platform

INDICATION, TARGET TRANSCRIPT, PRODUCT PROFILE SPLICING RNAi ANTISENSE DEFINE MODALITY DESIGN & OPTIMIZE VALIDATE SEQUENCE STEREOCHEMISTRY CHEMISTRY Free uptake in cellular models Animal models POTENCY STABILITY SPECIFICITY IMMUNE POTENCY

DURABILITY TOXICOLOGY Candidates

INDICATION, TARGET TRANSCRIPT, PRODUCT

PROFILE SPLICING RNAi ANTISENSE DEFINE MODALITY DESIGN & OPTIMIZE VALIDATE SEQUENCE STEREOCHEMISTRY Free uptake in cellular models Animal models POTENCY STABILITY SPECIFICITY IMMUNE POTENCY DURABILITY TOXICOLOGY Candidates CHEMISTRY Wave's

chemistry platform: Antisense

Precision RNase H-mediated RNA

degradation Antisense In RNase H1 assay, ASOs were pre-annealed to surrogate MALAT1 mRNA (1:1, Cf=5 mM). RNase H (250:1, E:S) was added and quenched with EDTA at the indicated times. Products were quantified, and V0 was calculated from the best-fit

line (n=3 per time point). RNA-Stereorandom ASO RNA-Stereopure ASO Rp Sp Rp or Sp Linker Nucleotide Initial Velocity (V0) Cleavage Activity

Potency of stereopure

oligonucleotides under in vitro free-uptake conditions translates in vivo In vitro: In iCell neurons, 10, 30, 100, 300, 1,000 or 3,000 nM ASO was added to iCell neurons under free-uptake conditions. 4-days post-treatment, RNA was harvested and

processed. MALAT1 mRNA expression was determined by qPCR (n=2 per concentration). In vivo: Mice received a single IVT injection. 1 week post-injection, tissues were frozen and processed for RNA. MALAT1 mRNA expression was determined by qPCR (n=7).

Antisense MALAT1 Knockdown in Posterior Mouse Eye at 1 Week MALAT1 Knockown in iCell Neurons In Vitro In Vivo

Stereopure oligonucleotides enhance

potency across tissues in vivo Muscle Single SC injection in Mice (25 mg/kg) Eye Single IVT injection in Mice (50 g) CNS Single ICV injection in Mice (50 g) Antisense Tissues were harvested 1 week post-dose and processed for RNA. mRNAs

were quantified by qPCR. Plots show relative fold change or percentage mRNA remaining with respect to control mRNA. Each symbol represents one animal. SR = Stereorandom

Stereopure oligonucleotides induce

potent and durable activity in the eye Tissues were harvested at the indicated time points, post-dose and processed for RNA. mRNAs were quantified by qPCR. Plots show percentage mRNA remaining with respect to control mRNA. Each symbol represents one

animal. 9-fold greater eye volume Antisense (OTS poster #030)

Stereopurity improves potency and

durability of GalNAc-conjugated oligonucleotides Antisense Stereopure ASO yields potency comparable to state-of-the-art GalNAc-dsRNAi Stereopure ASO yields durable effect in transgenic mice

INDICATION, TARGET TRANSCRIPT,

PRODUCT PROFILE SPLICING RNAi ANTISENSE DEFINE MODALITY DESIGN & OPTIMIZE VALIDATE Free uptake in cellular models Animal models POTENCY STABILITY SPECIFICITY IMMUNE POTENCY DURABILITY TOXICOLOGY SEQUENCE STEREOCHEMISTRY CHEMISTRY Candidates

Wave's chemistry platform: Splicing

Stereopure oligonucleotides induce

exon 23 skipped transcript (OTS poster #119) Splicing Stereorandom (SR) Stereopure

Stereopure oligonucleotide induces

dystrophin protein restoration and reduces elevated serum enzymes Splicing Multiple Doses (in vivo mdx23 mice) 70-90% of natural dystrophin restoration 87% reduction in creatine kinase levels ALT=alanine aminotransferase; AST=aspartate

aminotransferase; CK=creatine kinase; GLDH=glutamate dehydrogenase. Serum and plasma clinical chemistry were measured with an Olympus AU640 (Olympus America) and the manufacturer's reagents and procedures. Dystrophin Protein Restoration Serum

Stereopure surrogate restores

dystrophin in muscle fibers after single dose Neuro DMD PBS DMD-1742 Immunohistochemistry of dystrophin in gastrocnemius in mdx23 mice at 4 weeks 10X Experimental conditions: mdx23 mice received a single IV injection of PBS or DMD-1742 (150 mg/kg).

Immunohistochemistry: Blue: Nuclei, Hoechest; Yellow: Rabbit anti-Dystrophin(#ab15277) 1:400 diluent, 555/Cy3, Yellow is a fake color for Cy3. 10X magnification.

Stereopure surrogate restores

dystrophin in muscle fibers after multiple doses Experimental conditions: mdx23 mice received 4 weekly IV injections of PBS or DMD-1742 (150 mg/kg). Immunohistochemistry: Blue: Nuclei, Hoechest; Yellow: Rabbit anti-Dystrophin(#ab15277) 1:400

diluent, 555/Cy3, Yellow is a fake color for Cy3. 10X magnification. Neuro DMD PBS DMD-1742 Immunohistochemistry of dystrophin in gastrocnemius in mdx23 mice at 4 weeks 10X 0X

Stereopure oligonucleotide traffics

to nuclei in myoblasts Cultured myoblasts were treated with 10 mM of the indicated ASO under free-uptake conditions. ASO was detected with ViewRNA; nuclei are stained with DAPI. Exon skipping efficiency was quantified by Taqman assay. Nuclear ASO

was quantified with ImageJ software (https://imagej.nih.gov/ij/). Stereorandom (SR) Stereopure Stereopure (opposite) Splicing Stereopure ASO enters the nuclei of cultured myoblasts and promotes efficient exon 51 skipping WV-3 SR WV-5

Mdx23 mice were treated with a

single 30 mg/kg dose of optimized, stereopure ASO (IV). Tissues were collected 24-hours post-dose. ASO was detected using ViewRNA, and nuclei were stained with Hoechst33342 or hematoxylin. Nucleus: Hematoxylin (blue) ASO: ViewRNA (red) Nucleus:

Hoechst33342 (blue) ASO: Fast Red (pink) Stereopure oligonucleotides access myofiber nuclei in mice Splicing Stereopure ASO targeting exon 53 rapidly enters myofibers in mdx23 mice 30 mg/kg, 24 hours Bright-field view Fluorescence-field view (z

We have developed a scalable process

for generating stereopure ASOs Compared with stereorandom, stereopure ASOs are: Taken up more readily by cells under gymnotic conditions in multiple cell lines More potent in multiple tissues More durable in vivo Optimized, stereopure ASOs exhibit

improvements in multiple properties: Precision and activity of RNase H Potency correlation between in vitro and in vivo Exon skipping efficiency Rapid and broad tissue distribution Nuclear uptake Summary

Future: Improving nucleic acid

therapeutics through greater understanding of protein-nucleic acid interactions Understanding innate immune receptor and broader DNA/RNA-protein interactions TLR9 bound to stereopure, CpG-containing oligonucleotide Stereochemistry of CpG-containing

oligonucleotides impacts TLR9 activity Fold-increase TLR9 signaling Concentration ASO (mM)

Future: More potent and durable CNS

targeting with new chemistries PBS = phosphate buffered saline; Ctx = cortex; Str = striatum; Cb = cerebellum; Hp = hippocampus; SC = spinal cord. PBS Stereopure Cortex Spinal cord 15.9 nM 150 nM 2,900 nM Stereopure Stereopure Stereorandom IC50

MALAT1 Knockdown in Mice 10 weeks after single 100 g injection MALAT1 Knockdown in Mice 1 week after single ICV injection MALAT1 Knockdown in Human iCell Neurons Under Free-Uptake Conditions Antisense In vitro potency In vivo potency In vivo