Corporate Presentation June 2013 Safe Harbor Statement During

Corporate Presentation June 2013

Safe Harbor Statement During the course of this presentation we will make statements that constitute forward-looking statements. These statements may include operating expense projections, the initiation, timing and results of pending or future clinical trials, the actions or potential action of the FDA, the status and timing of ongoing research, corporate partnering activities and other factors affecting Adherex Technologies’ financial condition or operations. Such forward looking statements are not guarantees of future performance and involve risk, uncertainties and other factors that may cause actual results, performance or achievements to vary materially from those expressed or implied in such statements. These and other risk factors are listed from time to time in reports filed with the SEDAR and the Securities and Exchange Commission, including but not limited to, reports on Forms 10 -Q and 10 -K. Adherex does not intend to update any forward looking information to reflect actual results or changes in the factors affecting forward-looking information.

Company Overview Biopharmaceutical company dedicated to the discovery and development of novel cancer therapeutics Two late stage oncology clinical products: Sodium Thiosulfate (STS) and Eniluracil (EU) STS: pending favorable data will file for NDA EU: pending partnering discussions advance to Phase III US based management team Headquarters in Research Triangle Park, NC Ticker: ADHXF – USA, AHX – Toronto Market Cap: $10 MM; 25. 1 MM shares outstanding $1. 9 MM in cash at 3/31/13, no debt Large insider ownership with aligned shareholder incentives

Management and Board of Directors Rosty Raykov – CEO Bear Stearns, Tiedemann Group, John Levin & Co. , Alchem and DCML Co. Robert Andrade – CFO Bear Stearns, JP Morgan, CIBC, Caxton Associates, Millennium Partners and DCML Co. David Lieberman – Chairman Donaldson, Lufkin & Jenrette, Tiedemann Group. Currently, an analyst with Southpoint Capital, Company’s largest shareholder. Chris Rallis – Director 30 years of business development, legal and operating experience at Wellcome and Triangle Pharmaceuticals. Currently, executive in residence with Pappas Ventures. Steve Skolsky – Director 30 years of operating experience, including Head of Glaxo Welllcome’s Division of HIV/Oncology, Chief Executive at Trimeris and Sequoia Pharmaceuticals. Currently, Global Head of Clinical and Data Operations at Quintiles.

STS Investment Highlights STS is a chemo-protectant agent being developed exclusively in children to prevent hearing loss caused by cisplatin Received Orphan Drug Designation in 2004 with 7 years exclusivity upon approval Phase III trial conducted by Children’s Oncology Group is fully enrolled with data on 135 patients expected in 3 Q 2013 Phase III trial conducted by SIOPEL 6 in children with liver cancer 76/102 patients enrolled Clinical trial costs covered by government grants Adherex has exclusive rights to data from both studies Potential for Rare Pediatric Disease Voucher: upon approval of STS 6 month priority review to any other new NDA or BLA application Voucher can be transferred or sold with no restrictions Intellectual property: Use-patent as chemo-protectant in-licensed from OHSU Issued European and Japanese patents expire 2021, US pending prosecution

Platinum Hearing Loss is Frequent, Severe and Irreversible Platinum drugs are major anti cancer agents in pediatric oncology Produce profound, irreversible, cumulative hearing loss Destroy the cochlear hair cells of inner ear Effect can be seen after as little as the second or third dose Hearing loss (ototoxicity) is a dose-limiting side effect Up to three thousand children receive platinum based chemotherapy every year in the US: 40 -90% develop irreversible ototoxicity Loss of high frequency hearing sensitivity - loss of high frequency consonants (s/f/th/p/k/h/t) Background noise compounds disability in critical settings - distance hearing and hearing in the classroom Infants and young children at critical stage of development lack speech language development and literacy Older children and adolescents lack social-emotional development and educational achievement

Ototoxicity in Children Treated with Cisplatin and/or Carboplatin Ototoxicity (%) 61% bilateral hearing loss (ASHA criteria) at the end of treatment 41% required hearing aids that only partially restore hearing 22% of patients had dose reductions due to ototoxicity N=67 age 8 m -20 years 100 80 88 75 67 60 50 40 20 11 0 Medulloblastoma Osteosarcoma Gilmer-Knight et al. , Journal of Clinical Oncology Neuroblastoma PNET Germ cell

Current Approach to Platinum Induced Hearing Loss Detected or Communicate d by Patient Detectable hearing loss generally begins after about two or three cycles of cisplatin, and may continue to occur for months (or longer) after use is discontinued Hearing Loss Diagnosed Continue Course Leads to more severe hearing loss Dose Modify Switch therapies Less effective dosing/treatment, potentially shortening survival

Target and Proposed STS Mechanism NH 3 NH Pt 3 Cl Protein Cl STS Cl Requires both Cl unbound to crosslink DNA Antitumor Effect Binding to plasma proteins occurs within first hour which inactivates one binding site Free c. DDP (unbound) short t 1/2 : 1. 5 hr Requires one Cl unbound to Ototoxicity Effect affect cochlear hair cells Binding to plasma proteins occurs within first hour which NH 3 inactivates one binding site Cl STS will bind second site Pt NH preventing ototoxicity 3 Cl Protein

STS Protects Against Cisplatin Ototoxicity in the Rat Change from baseline hearing threshold. Effect of STS (8 g/m 2 IV) 4 hrs, 8 hrs, or 12 hrs after administration of cisplatin (6 mg/kg IA) Delayed administration of STS after platinum agents in animals reduces ototoxicity

Cisplatin and STS animal PKs Cisplatin clearance is complete by 6 hrs with or without STS, when STS levels are at or higher than clinically achievable levels Cisplatin Pharmacokinetics nu/nu mice administered 4 mg/kg CDDP i. p. STS Pharmacokinetics nu/nu mice administered 3. 5 g/kg STS i. p. Level 1 min 15 min Mouse # 1 222. 0 mg/d. L 941. 0 mg/d. L Mouse # 2 180. 0 mg/d. L 5. 85 mg/d. L Mouse # 3 133. 5 mg/d. L n/a Mouse # 4 145. 8 mg/d. L 1131. 0 mg/d. L Mouse # 5 not detectable 1246. 0 mg/d. L Mouse # 6 177. 1 mg/d. L 975. 0 mg/d. L *Clinical peak STS level 15 min post-drug administration is approximately 330 mg/d. L.

Time-Dependent Tumor Protection of STS after Administration of Cisplatin in Nude Mice STS allows for anti-tumor activity when given properly Harned TM et al. Clin Cancer Res 2008; 14: 533 -540

COG ACCL 0431: Randomized Study of STS for Prevention of Cisplatin-induced Hearing Loss Newly diagnosed children with hepatoblastoma, germ cell tumor, osteosarcoma, neuroblastoma, and medulloblastoma Study Chair: David Freyer, DO, MS 135 randomized patients fully enrolled and study completed in 1 Q 2012 Futility analysis conducted and reviewed by COG DSMC August 2011 with recommendation at the time to continue study Expect data in 3 Q 2013

COG ACCL 0431: Randomized Study of STS for Prevention of Cisplatin-induced Hearing Loss Note: Patient must first be enrolled on the COG hearing assessment study, ACCL 05 C 1 Newly diagnosed germ cell tumor, hepatoblastoma, medulloblastoma, neuroblastoma, or osteocarcoma Diagnosis Planned treatment program includes 200 mg/m 2 cisplatin (administered according to the disease-specific regimen) Study entry onto ACCL 0431 Randomization Sodium thiosulfate given intravenously over 15 minutes starting 6 hours after completion of each cisplatin infusion (STS Arm) No sodium thiosulfate treatment given (Observation Arm) Protocol therapy ends when patient completes planned treatment regimen containing cisplatin Audiology done with each cycle of therapy 80% power to detect 22. 5% vs 45% change in hearing 80% power to rule out >12% difference in 3 yr EFS Secondary objectives measurement of nephrotoxicity and neurotoxicity

SIOPEL 6: Efficacy of STS in Reducing Ototoxicity in Patients Receiving Cisplatin for Standard Risk Hepatoblastoma Newly diagnosed children with standard risk hepatoblastoma Study Chair: Peppy Brock, MD 78 randomized patients fully enrolled out of 102 Interim evaluations of efficacy of the chemotherapy carried out and reviewed by IDMC after 20, 40, 60 and 80 patients are evaluable for response Early stopping will be considered in case of concerns on efficacy of chemotherapy in either treatment arm The first two interim safety analysis after 20 and 52 patients were conducted with IDMC recommending study to continue Two interim and one final efficacy analyses planned for early stopping in case of a greater than expected difference between treatment arms in terms of hearing loss *Next interim analysis expected by mid-2014

SIOPEL 6: Efficacy of STS in Reducing Ototoxicity in Patients Receiving Cisplatin for Standard Risk Hepatoblastoma Diagnostic biopsy Tumour storage Radiological staging RRR if required Registration to remote data entry site via web R A N D O M I S A T I O N CDD P STS CDD P STS c. DDP: 80 mg/m 2 STS: 10 -20 gm/m 2 depending on age/weight CDD P STS 80% power to detect 60% vs 35% hearing loss Two interim and one final efficacy analyses planned for early stopping in case of a greater than expected difference between treatment arms in terms of hearing loss CDD P STS D E L A Y E D S U R G E R Y CDD P STS

STS: Development Timeline Event FDA Type C Clinical Development Meeting Timing Presented to Pediatric ODAC March 2011 ODAC recognized challenge of demonstrating STS does not reduce efficacy of cisplatin and agreed adult study would not be appropriate Nov 2011 COG ACCL 0431 Clinical Data 3 Q 2013 FDA Type C Clinical Meeting – Agree COG Data Acceptable for NDA H 1 2014 FDA Pre NDA Meeting mid 2014 NDA Submission 1 Q 2015

STS Market Opportunity Pediatric Market Opportunity 12, 000 children develop cancer in the US every year 2, 000 children will receive platinum-based chemotherapy, 3 x ROW Pricing to be determined based on available therapies in the market Competitive Position Significance of injury increases value of STS Limited competition – hearing aids and cochlear implants do not prevent hearing loss Hearing aids cost $2000 to $6000 each Cochlear implants cost up to $75, 000 each Third party market research shows strong adoption characteristics Physician approval very high Payors feedback positive

Summary STS has Two Potential Near Term Value Drivers Positive data from COG Phase III trial will support filing of NDA Upon approval of NDA, receipt of Rare Pediatric Disease Voucher Eniluracil is active and well tolerated Indications where 5 -FU is administered potentially in excess of $1 BLN market Seek partnership for further development of Eniluracil Third party market research shows strong adoption characteristics With convincing data from COG Phase III trial submit for NDA Further development of Eniluracil