FENNEC PHARMACEUTICALS INC. — Director's Dealing 2007

May 2, 2007

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: ADHEREX TECHNOLOGIES INC (AMEX:ADH)
CIK: 0001211583
Period of Report: 2007-04-30

Reporting Person: Mermelstein Fred H (Director)

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2007-04-30	Stock Options (Right to buy)	$0.63	A	230000	Acquired	2014-04-30	Common Stock (230000)	Direct

Holdings (Non-Derivative)

Security	Shares	Ownership
Common Stock	35591	Direct
Common Stock	1327819	Indirect

Holdings (Derivative)

Security	Exercise Price	Expiration	Underlying	Shares	Ownership
Stock Options (Right to buy)	$0.28	2014-02-28	Common Stock (50000)	50000	Direct
Stock Options (Right to buy)	$1.2	2012-05-18	Common Stock (18621)	18621	Direct
Stock Options (Right to buy)	$1.2	2012-09-21	Common Stock (30000)	30000	Direct
Stock Options (Right to buy)	$1.7	2010-05-03	Common Stock (7800)	7800	Direct
Stock Options (Right to buy)	$2.9	2011-05-21	Common Stock (4000)	4000	Direct
Stock Options (Right to buy)	$3.25	2011-03-01	Common Stock (18621)	18621	Direct
Warrants (Right to buy)	$2.15	2008-12-19	Common Stock (23078)	23078	Direct
Warrants (Right to buy)	$3.585	2007-11-20	Common Stock (76384)	76384	Indirect

Footnotes

F1: The options to which this note relates are subject to vesting in three (3) installments with one-third vesting immediately and the remaining shares vesting on the first and second anniversary of the Grant Date reported above.