Announcing FDA Approval of GOCOVRI TM

Forward-looking Statements Statements contained in this presentation regarding expected future events are forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995, including but not limited to, statements contained in this presentation regarding the expected benefits of GOCOVRI, physician and patient access in fourth quarter 2017 and launch of GOCOVRI (amantadine) extended release capsules (previously ADS-5102) in January 2018 for the treatment of dyskinesia in patients with Parkinson s disease receiving levodopa-based therapy, with or without concomitant dopaminergic medications, and Adamas plans to offer a number of programs providing patient access support throughout the course of treatment, along with commercial copay assistance and financial assistance for patients who are uninsured or underinsured. Words such as potentially, expected, will, plans and similar expressions (as well as other words or expressions referencing future events, conditions, or circumstances) are intended to identify forward-looking statements. Because such statements are subject to risks and uncertainties, actual results may differ materially from those expressed or implied by such forward-looking statements. For a description of risks and uncertainties that could cause actual results to differ from those expressed in forward-looking statements, including risks relating to Adamas research, clinical, development, and commercial activities relating to ADS-5102 and ADS- 4101, and the regulatory and competitive environment and Adamas business in general, see the Section captioned Risk Factors in Adamas Quarterly Report on Form 10-Q filed with the Securities and Exchange Commission on August 8, 2017. Investors are cautioned not to place undue reliance on these forward-looking statements, which speak only as of the date of this release. Adamas undertakes no obligation to update any forward-looking statement in this press release. 2017 Adamas Pharmaceuticals, Inc. All Rights Reserved. 2

Dyskinesia in People with Parkinson s Disease Involuntary, non-rhythmic movements that are purposeless and unpredictable Struggle to balance dyskinesia and with OFF time Frustration, embarrassment, isolation Poor quality of life, increased care burden Risk of injury, social withdrawal, depression Affecting 150,000 200,000 people in the United States 2017 Adamas Pharmaceuticals, Inc. All Rights Reserved. 4

First and only FDA-approved medicine for treatment of dyskinesia in patients with Parkinson s disease receiving levodopa-based therapy, with or without concomitant dopaminergic medicines 2017 Adamas Pharmaceuticals, Inc. All Rights Reserved. 5

GOCOVRI Clinical Program Overview 8-week Dose Ranging (EASED) Study 1 (EASE LID) Study 2 (EASE LID 3) Randomized, 4-arm, placebo-controlled trial 80 in mitt, 8-wks duration Randomized, 2-arm, placebo-controlled trial 121 in mitt, 25-wks duration Randomized, 2-arm, placebo-controlled trial 75 in mitt, 13-wks duration Primary outcome measure: UDysRS Key secondary outcome measures: - ON time without troublesome dyskinesia (functional time) - OFF time Open Label (EASE LID 2) Open-label safety study 223 subjects (Ongoing), Up to 2-yrs duration 2017 Adamas Pharmaceuticals, Inc. All Rights Reserved. 6

Change in UDysRS Total Score (LS Mean ± SE) GOCOVRI Delivered Statistically Significant Reductions in Dyskinesia Study 1, GOCOVRI provided a 37% reduction in Unified Dyskinesia Rating Scale (UDysRS) total score vs. 12% for placebo at Week 12 Reduction in dyskinesia was evident at the first post-baseline assessment Week Week Week Week Baseline 2 4 6 8 10 12 0 Percent Improvement at 12 weeks -5-10 -8.0 12% 37% -15-20 -15.9 P=0.0009-25 Placebo (n=58) GOCOVRI (n=63) 2017 Adamas Pharmaceuticals, Inc. All Rights Reserved. 7

Change in UDysRS Total Score (LS Mean ± SE) Significant Reductions in Dyskinesia Confirmed in Second Pivotal Study Study 2, GOCOVRI-treated patients demonstrated a 46% reduction in UDysRS total score vs. 16% for placebo at Week 12 Week Week Week Week Baseline 2 4 6 8 10 12 0 Percent Improvement at 12 weeks -5-6.3 16% -10 46% -15-20 -20.7-25 Placebo (n=38) GOCOVRI (n=37) P<0.0001 2017 Adamas Pharmaceuticals, Inc. All Rights Reserved. 8

LS Mean Change from Baseline (hrs) LS Mean Change from Baseline (hrs) GOCOVRI-Treated Patients Gained 3.6 Hours of Functional Time Daily* Study 1, increased functional time due in part to a placebo-adjusted 1-hr decrease in OFF time and reductions in ON time with troublesome dyskinesia ON time w/o troublesome dyskinesia OFF time 4 3 3.6 4 3 2 2 1 0-1 Baseline 2 4 6 8 10 12 Week Placebo (n=58) GOCOVRI (n=63) 0.8 P<0.0001 1 0 P=0.0171 0.3-0.6-1 Baseline 2 4 6 8 10 12 Week Placebo (n=58) GOCOVRI (n=63) LS = Lease Squares. *As defined by ON time without troublesome dyskinesia. Results derived from PD Home Diary Data. 2017 Adamas Pharmaceuticals, Inc. All Rights Reserved. 9

LS Mean Change from Baseline (hrs) LS Mean Change from Baseline (hrs) Increased Functional Time* Confirmed in a Second Pivotal Study Study 2, GOCOVRI provided a placebo-adjusted 1.1 hour decrease in OFF time daily ON time w/o troublesome dyskinesia OFF time 5 5 4 3 4.0 4 3 2 1 0-1 Baseline 2 4 6 8 10 12 Week Placebo (n=38) GOCOVRI (n=37) 2.1 P=0.0168 2 1 P=0.0199 0.6 0-0.5-1 Baseline 2 4 6 8 10 12 Week Placebo (n=58) GOCOVRI (n=63) LS = Lease Squares. *As defined by ON time without troublesome dyskinesia. Results derived from PD Home Diary Data. 2017 Adamas Pharmaceuticals, Inc. All Rights Reserved. 10

Warnings/Precautions and Adverse Reactions Warnings / Precautions Falling asleep during activities of daily living and somnolence Suicidality and depression Hallucinations / psychotic behavior Dizziness and orthostatic hypotension Withdrawal emergent hyperpyrexia and confusion Impulse control / compulsive behaviors Common Adverse Reactions (>10%) vs. placebo Hallucination (21% v. 3%) Dizziness (16% v. 1%) Dry mouth (16% v. 1%) Peripheral edema (16% v. 1%) Constipation (13% v. 3%) Falls (13% v. 7%) Orthostatic hypotension (13% v. 1%) Please see full prescribing information at www.gocovri.com 2017 Adamas Pharmaceuticals, Inc. All Rights Reserved. 11

Dosage and Administration GOCOVRI is a high-dose 274 mg amantadine taken once-daily at bedtime that delivers consistently high levels of amantadine in the morning and throughout the day when dyskinesia occurs Administer orally once-daily at bedtime The initial daily dosage is 137 mg; after 1 week, increase to the recommended daily dosage of 274 mg Swallow whole; may sprinkle contents on soft food May be taken with or without food; avoid use with alcohol A lower dosage is recommended for patients with moderate or severe renal impairment GOCOVRI is contraindicated in patients with End Stage Renal Disease Please see full prescribing information at www.gocovri.com 2017 Adamas Pharmaceuticals, Inc. All Rights Reserved. 12

First and only approved medicine for treatment of dyskinesia in patients with Parkinson s disease receiving levodopa-based therapy, with or without concomitant dopaminergic medicines 2017 Adamas Pharmaceuticals, Inc. All Rights Reserved. 14

GOCOVRI is Well Received by Physicians Physicians report intent to use in 54% of dyskinetic Parkinson s patients Share of dyskinesia patients to GOCOVRI (by source) Instead of addition of another Product 23 47 ~150-200K Parkinson s disease patients in U.S. suffer with dyskinesia HCPs indicated that 54% of dyskinesia patients would be prescribed GOCOVRI Instead of C/L fractionation / dosage adjustment 10 16 Share would come from: Untreated dyskinesia patients 24% For untreated dyskinesia patients taking C/L 13 37 Instead of C/L fractionation or dose adjustment 6% Prescribe GOCOVRI 54 Instead of other therapies (AMT IR, dopamine agonist, COMT inhibitor, MAO-B Inhibitor) 24% 0 20 40 60 Payers appreciate value proposition After GOCOVRI Before GOCOVRI C/L = Carbidopa / Levodopa Quantitative Research among 138 HCP s treating Parkinson's Disease (MDS and Neurologist), Fielded Q1 2017 Question asked: Assuming the FDA-approval of Product X, how would you anticipate your overall treatment of ALL levodopa-induced dyskinesia patients to change in the next 12 months? 2017 Adamas Pharmaceuticals, Inc. All Rights Reserved. 15

GOCOVRI Launch Preparations Launch Medical Information Hotline GOCOVRI Available GOCOVRI Launch Announce Price of GOCOVRI Launch Patient Access Support (GOCOVRI Onboard) Speaker Training September October November December January Key Account Managers Deployed Medical Science Liaisons Deployed Training, Appointment Scheduling 6 Regional Business Directors Start 59 Neurology Account Specialists Start 2017 Adamas Pharmaceuticals, Inc. All Rights Reserved. 16

Adamas Portfolio Disease Program Phase 1 Phase 2 Phase 3 Commercial Commercial Lead Dyskinesia in Parkinson s Disease Multiple Sclerosis Walking Parkinson s disease Additional Indication GOCOVRI (amantadine) ADS-5102 (amantadine) ADS-5102 (amantadine) Epilepsy Partial Onset Seizures ADS-4101 (lacosamide) Alzheimer s Dementia NAMENDA XR (memantine HCl) NAMZARIC (memantine HCl & donepezil HCl) (US) NAMENDA XR and NAMZARIC are trademarks of Merz Pharma GmbH & Co. KGaA. 2017 Adamas Pharmaceuticals, Inc. All Rights Reserved. 18