Innovation Today, Healing Tomorrow.

June 2017

CORPORATE OVERVIEWNASDAQ: GLYC

Forward-Looking Statements

To the extent that statements contained in this presentation are not descriptions of historical facts regarding

GlycoMimetics, Inc. (“GlycoMimetics,” “we,” “us,” or “our”), they are forward-looking statements reflecting

management’s current beliefs and expectations. Forward-looking statements are subject to known and unknown

risks, uncertainties, and other factors that may cause our or our industry’s actual results, levels of activity,

performance, or achievements to be materially different from those anticipated by such statements. You can

identify forward-looking statements by terminology such as “may,” “will,” “should,” “expects,” “plans,”

“anticipates,” “believes,” “estimates,” “predicts,” “potential,” “intends,” or “continue,” or the negative of these

terms or other comparable terminology. Forward-looking statements contained in this presentation include, but are

not limited to, statements regarding: (i) the conduct of the ongoing Phase 3 clinical trial of GMI-1070 by Pfizer Inc.

(“Pfizer”); (ii) the timing of additional clinical trials for our other drug candidates; (iii) the timing of receipt of clinical

data for our drug candidates; (iv) our expectations regarding the potential safety, efficacy, or clinical utility of our

drug candidates; (v) the size of patient populations targeted by drug candidates we or our collaborators develop

and market adoption of our potential drugs by physicians and patients; (vi) the likelihood and timing of regulatory

filings and approvals; and (vii) and our cash needs and potential royalties and milestone payments under license

and collaboration agreements.

Various factors may cause differences between our expectations and actual results, including unexpected safety

or efficacy data, unexpected side effects observed during preclinical studies or in clinical trials, lower than

expected enrollment rates in clinical trials, changes in expected or existing competition, changes in the regulatory

environment for our drug candidates, failure of our collaborators to support or advance our collaborations or drug

candidates, our need for future capital, the inability to protect our intellectual property, and the risk that we

become a party to unexpected litigation or other disputes. For a further description of the risks associated with

forward-looking statements, as well as other risks facing GlycoMimetics, please see the risk factors described in the

Company’s Annual Report on Form 10-K filed with the U.S. Securities and Exchange Commission on March1, 2017,

as well as other reports we file with the U.S. Securities and Exchange Commission from time to time, including those

factors discussed under the caption “Risk Factors” in such filings. Forward-looking statements speak only as of the

date of this presentation, and GlycoMimetics undertakes no obligation to update or revise these statements,

except as may be required by law.

2

GlycoMimetics - Investment Opportunity

Highly differentiated clinical programs for orphan diseases

– Portfolio targets significant unmet needs with large commercial potential

Phase 3 in vaso-occlusive crisis (VOC) of sickle cell disease

– Robust Phase 2 results across all endpoints

– Phase 3 top-line results expected 2H 2018

– Partnered with Pfizer

Phase 2 in acute myeloid leukemia

– Compelling clinical outcomes and biomarker proof-of-concept from ongoing Phase 1/2 trial

– Multiple data readouts next 6-12 months

Proven management team

– Pioneers in the field of glycobiology, with broad experience in drug development

Strong Balance Sheet provides funding through multiple milestones

3

Major Announcements & Upcoming Milestones

4

Rivipansel (Phase 3)

Phase 2 data selected as “Best of ASH” ✓

Orphan Drug Designation & Fast Track Status (US) ✓

Special Protocol Assessment with FDA ✓

Phase 3 enrollment initiated ✓

Anticipate announcing Phase 3 top-line results 2H-2018

GMI-1271 (Phase 1/2)

Orphan Drug Designation (US & EU) & Fast Track Status (US) ✓

Completion of Phase 1 and selection of phase 2 dose ✓

Completion of Phase 2 enrollment in newly diagnosed AML cohort ✓

Breakthrough Therapy Designation granted by the FDA ✓

Completion of Phase 2 enrollment in R/R AML cohort ✓

Presentation of interim Phase 2 results at ASCO and EHA ✓

Define registration program in AML with regulatory agencies Q4’17 - ‘18

Anticipate announcing Phase 2 durability of response and OS Q4’17 - ‘18

GMI-1359 (Phase 1)

Initiation of Phase 1 study ✓

Anticipate announcing optimal dose and initial cancer indication Q4’17 - ‘18

A Balanced Portfolio of Product Candidates

5

Compound Therapeutic Area Discovery Pre-Clinical

Ph 1 Ph 2 Ph 3 Registration Partner

Selectins

Rivipansel(Pan-selectin Inhibitor)

Sickle Cell Anemia Vaso-occlusive Crisis Pfizer

GMI-1271 and Follow-ons(E-selectin Inhibitor)

Acute MyelogenousLeukemia

--

Multiple Myeloma --

Various Tumor Types & Inflammatory Diseases

--

GMI-1359(E-selectin & CXCR4 Inhibitor)

Various Tumor Types --

Galectins

Galectin-3Inhibitor

Fibrosis & Oncology --

Undisclosed GalectinInhibitor

Various Tumor Types --

GMI-1271

Targeting the Bone Marrow

Microenvironment for

Treatment of AML

6

GMI-1271: A First-in-Class Therapeutic Disrupts

Tumor Microenvironment

Small-molecule, potent, selective, E-selectin antagonist

Compelling efficacy, safety and biomarker data from Phase 1/2 AML

study - clinical proof-of-concept established

– High remission rates, low induction mortality and promising initial

survival in highly pre-treated R/R AML population

• Biomarker correlated with achievement of remission

– High remission rates and low induction mortality in newly

diagnosed, elderly, AML patients

– Benign safety profile with observed reductions in chemotherapy-associated toxicities (e.g. mucositis)

Preclinical rationale for use in multiple indications and combination

approaches - “proteasome-rescue” study underway in MM

IP through 2032

7

Study Design

– Dose Escalation: 3 dose levels tested (5, 10 & 20 mg/kg) in

Relapsed/refractory AML (MEC) population

• Phase 2 dose selected - 10mg/kg

– Dose Expansion:

• 25 patients with newly diagnosed AML > 60 (7&3)

• 47 patients with R/R AML (MEC)

Endpoints: Safety, PK, Biomarkers & Efficacy (ORR)

Lead Investigator: Dan DeAngelo, MD, PhD – Dana Farber Cancer Institute

– Additional centers in US, Ireland and Australia

GMI-1271 Phase I / II Study in AML

Treatment Follow-Up

BM Biopsy

Screening

-22 to 0 15 28Visit DayGMI-1271 + Chemo

GMI-1271 GMI-1271

Long-Term Follow-Up

6 Mon 12 Mon

8

Re-TreatmentPhase 2 Expansion

✓

✓

✓

High-risk, heavily pre-treated patient

population

– All patients had intermediate or

unfavorable cytogenetics

– >60% were either refractory or early

relapsed (<6 months) AML

Higher than expected CR/CRi rate and

promising initial median overall survival

– mOS 7.6 mons vs. ~5.4 mons (MEC-alone)

– Baseline expression of E-selectin ligand is

predictive of remission

– For responders in Phase 1, median

survival not reached at 12+ months

GMI-1271 + MEC well tolerated

– No DLTs observed - AE profile consistent

with MEC alone

Signs of protective effects - oral mucositis

/stomatitis occurred at lower rates and

intensity than expected for MEC (2% incidence

Grade 3/4 vs. 25% for historical MEC-alone)

9

Key Phase I / II Interim Results

in R/R AML Population

Clinical proof-of-concept established

Complete Remission Rate

‡ Response criteria per Cheson, 2003; Dohner 2010.Feldman J Clin Oncol 2005 Jun 20:23 (18): 4110-6.

Percent of Patients

CR + CRi

28

41

0 20 40 60

MEC(Feldman)

GMI-1271

Elderly, high-risk patient population

– 50% had sAML; >92% had

intermediate - unfavorable

cytogenetics

GMI-1271 + 7&3 well tolerated

– AE profile consistent with 7&3 alone -

no obvious incremental toxicity

– 0% grade 3-4 mucositis

E-selectin ligand broadly expressed at

baseline in majority of patients - target

clinically relevant

Efficacy data compares favorably to well-

established historical controls (7&3 or

Vyxeos)

– Responses appear durable with100%

of responding patients remaining in

remission at 6 months

10

Key Phase II Interim Results

in Frontline AML Population

Promising Complete Remission Rates in High-Risk, Elderly AML Patients

Percent of Patients

Complete Remission Rate

‡ Response criteria per Cheson, 2003; Dohner 2010.Foran et al. Blood 2015 126:217.Lancet et al. ASCO Annual Meeting 2016.

48

63

44

68

0 20 40 60 80

Vyxeos (Phase 3)

GMI-1271 sAML

(10mg/kg)

7 & 3 (Foran)

GMI-1271 Newly

Diagnosed (10mg/kg)

CR + CRi

GMI-1271-201: Overall Response by Cytogenetic

& Other Risk Factors

Remission Rates (CR/CRi) in Defined Subgroups, n (%)

AML SubgroupPhase 1 R/R

(MEC)

Phase 2 R/R

(MEC)

RP2D R/R

(MEC)

Total R/R

(MEC)

Elderly

Newly

Diagnosed

(7+3)

N Completing Induction

Period19 35 42 54 25

Favorable risk (SWOG) 0 0 0 0 1/1 (100%)

Intermediate risk (SWOG) 5/9 (56%) 6/15 (40%) 9/17 (53%) 11/24 (46%) 10/15 (67%)

Unfavorable risk (SWOG) 4/10 (40%) 7/22 (32%) 9/23 (39%) 11/32 (34%) 5/8 (63%)

FLT3-ITD mutated 1/2 (50%) 2/5 (40%) 3/7 (43%) 3/7 (43%) 1/1 (100%)

Extramedullary disease 1/1 (100%) 1/1 (100%) 2/2 (100%) 2/2 (100%) 0

11

Higher than expected remission rate maintained across all subgroups,

including those with unfavorable risk

% E

-Se

lec

tin

(H

EC

A-4

52)

Po

sitiv

e A

ML

Bla

sts

PD+PR+

MLFS+CRi

CR

PD+PR+MLFS+

CRiCR

N 17 8

Mean 22.13 48.89

Median 24.56 50.39

Min 0.86 14.87

Max 60.65 76.21

Lower 95% CI

12.57 31.11

Upper 95% CI

31.70 66.66

P=0.0039

0

20

40

60

80

100

Relapse/Refractory Cohort: Correlation of Baseline

E-Selectin Expression And Clinical Remission

12

GMI-1271: US Regulatory Update & Future Plans

Breakthrough Therapy Designation (BTD) granted “for the treatment of

adult patients with relapsed/refractory acute myeloid leukemia” on

May 17, 2017

– BTD expedites the development and review of new medicines that

• treat Serious or life-threatening disease

• demonstrate substantial improvement over existing therapy

US Fast Track status granted in June 2016

Orphan Drug Designation (USA May 2015 / Europe May 2016)

13

Potential for expedited development program and

FDA regulatory review

GMI-1271:

Scientific Rational for Use in Multiple

Myeloma

14

High ST3GAL6/low FUCA1

FISH/ISS others

E-Selectin Expression is Associated with Poorer

Clinical Outcomes in Multiple Myeloma

15

NDMM: Newly

Diagnosed

(n=33)

rrMM:

Relapsed/Refractory

(n=50)

E-Selectin Expression Overall Survival

E-selectin ligand is over-expressed in high risk MM patients and confers poor

prognosis (e.g. mOS of 10 months vs. 33 months)

A. Natoni et al. Leukemia.2017.123

16

Addition of GMI-1271 Restores Sensitivity of Bortezomib

in an E-Selectin Overexpressing Model of MM

0 20 40 60 800

50

100

Days post tumor injection

Pe

rce

nt

su

rviv

al

0 50 100 1500

50

100

Days post tumor injection

Pe

rce

nt

su

rviv

al

TreatmentMST

(days)%

survival P vs

saline

saline 33 0

GMI-1271(40 mg/kg IP qd x 21 days

31 0

Bortezomib(0.75 mg/kg IP qw x 3 wks

42 0 0.0622

GMI-1271 + Bortezomib 60b 0 0.0101

TreatmentMST

(days)%

survival P vs

saline

saline 25.5 0

GMI-1271(40 mg/kg IP qd x 21 days

30 0

Bortezomib(0.75 mg/kg IP qw x 3 wks

24 0

GMI-1271 + Bortezomib 56.5c 37.5 0.0028

aP=0.0363 vs. bortezomib

aP=0.0123 vs. bortezomib

Parent

E-Selectin

Enriched

aadditional study at lower tumor inoculum gives similar outcome

A. Natoni et al. Leukemia.2017.123

Study Design: Phase I Dose Escalation

– Patient Population

• Patients with relapsed/refractory MM continuing on

bortezomib/carfilzomib-based regimen

– 4 Dose Levels (5, 10 & 20 mg/kg) - 6 patients/Cohort

• Weekly or Bi-weekly bortezomib/carfilzomib backbone

Endpoints: Safety, PK, Biomarkers & Efficacy

Lead Investigator: Michael O’Dwyer, MD: NUI – Galway

Proof-of-Concept Study in MM Ongoing

“Proteasome Inhibitor Rescue”

Bort/Carf

Baseline

17

Screening Treatment (Up to 6 Cycles)

Weekly or Bi-Weekly Standard Regimen Bortezomib/Carfilzomib

QD dosing same time and 24 hrs following each dose of Bort/CarfGMI-1271

Follow-Up

Bone Marrow

Biopsy

Cycle 3 Cycle 6 Folllow-Up

Rivipansel (GMI-1070) for

Sickle Cell Crisis

18

Rivipansel Value Proposition

Significant unmet medical need

Quantifiable clinical and health-

economic endpoints

Defined regulatory path to approval

– US FDA Special Protocol

Assessment

Excellent economics to GLYC from

Pfizer

19(1) Hassell KL. (2010) Am J Prev Med.;38(4 Suppl):S512-21

(2) Brousseau D et. al. (2010) Am J Hematol. 85(1) 77-8

(3) Yusuf HR et. al. (2010) Am J Prev Med. 38(4 0)

Initial US Approval Goal

Inpatient Hospitalizations

(80-100,000 Events/Yr1,2)

Outpatient Treatment

in ER & Clinic Settings (~140,000 Events/Yr3)

Attractive commercial opportunity; substantial market expansion potential

– On-demand approach

• Avoids historical noncompliance challenges with chronic, prophylactic

therapy

– Longer term potential: Treat VOC earlier in ER/clinic

Sickle Cell Anemia Healthcare

Utilization for VOC

Rivipansel Clinical Development Highlights

Improvements observed in

every efficacy endpoint

evaluated across all

subgroups studied in Phase

2 study

– Reduction in time in to

hospital discharge by

> 3.5 days

Efficacy data supported by

improvements on

biomarkers of inflammation

and coagulation in

patients in biomarker study

Benign safety profile

Phase 2 data recognized

as “Best of ASH”

Rivipansel

Placebo

Pro

ba

bili

tyTime to Discharge (Hours)

0 50 100 150 200

1.0

0.8

0.6

0.4

0.2

0.0

Median time to discharge

reduced by 84 hours

(p=0.092; Kaplan-Meier)

Time to Discharge From Hospital

20Telen, Blood. 2015 Apr 23;125(17):2656-64

Phase 2 Results – Substantial Reduction in

Time to Resolution of VOC and Opioid Use

Ho

urly IV

Op

ioid

Use

Mean Hourly Opioid Use

0.0

0.2

0.4

0.6

0.8

1.0

Day 1 Day 2 Day 3 Day 4 Day 5 Day 6 Day 7

Rivipansel

Placebo

24 hour reduction p<0.001***

Cumulative opioid analgesic

administered reduced by 83%

(p=0.010; ANCOVA)

21

Opioid Use Over Time

Rivipansel

Placebo

Pro

ba

bili

ty

Time to Resolution (Hours)

0 50 100 150 200

1.0

0.8

0.6

0.4

0.2

0.0

Median time to resolution of VOC

reduced by 63 hours

(p=0.187; Kaplan-Meier)

Time to Resolution of VOC

Telen, Blood. 2015 Apr 23;125(17):2656-64

Tiered, ranging from low double digits to low teens

Total Milestones: up to $320.0 million

Development: up to $115.0 million

$35.0 million upon start of Phase 3

$15.0 million advance payment received in May 2014,

$20.0 million received August 2015 with dosing of the first

patient.

Regulatory: up to $70.0 million

Commercial: up to $135.0 million

$22.5 million

Pfizer responsible for all further clinical development, regulatory approval and potential commercialization for all indications worldwide

Rights

Upfront

Milestones

Royalties

Pfizer Deal Economics

22

GlycoMimetics is Positioned for Success

23

Promising Pipeline

Rivipansel: Sole “on-demand” treatment in late-stage,

registration trial for acute VOC; SPA in place with FDA

GMI-1271: Clinical outcomes and biomarker demonstrate

clinical proof-of-concept in AML; Breakthrough Therapy

Designation granted by the FDA

GMI-1359: Simultaneous blockade of CXCR4 & E-Selectin

inhibits established pathways of cancer cell trafficking

Significant Revenue

Opportunities

Rivipansel: ~100,000 patients in USA

GMI-1271: > 40,000 AML patients in 7MM

Strong Investment BaseCash balance provides runway through key milestones

Top-tier biotech investors

Experienced Team

Pioneers in the field of glycobiology and small-molecule,

therapeutic “mimetics”Relationships with leading KOLs and national / international

oncology networks

Innovation Today, Healing Tomorrow.

June 2017

CORPORATE OVERVIEWNASDAQ: GLYC