Alder BioPharmaceuticals® Reports Inducement Grant Under Nasdaq Listing Rule 5635(c)(4)

Alder BioPharmaceuticals, Inc. (Nasdaq: ALDR), a biopharmaceutical company focused on developing novel therapeutic antibodies for the treatment of migraine, today reported that the Compensation Committee of Alder’s Board of Directors granted a non-qualified stock option to purchase an aggregate of 40,000 shares of Alder’s common stock to a new employee under Alder’s 2018 Inducement Award Plan, effective October 1, 2018.

The stock option will vest with respect to 25% of the shares underlying the option one year after the employee’s employment start date and the remaining 75% of the shares underlying the option will vest in equal monthly installments over the 36 month period following the one year anniversary of the employee’s employment start date, subject to the employee’s continued service to Alder through each relevant vesting date. The option has a ten year term and an exercise price of $14.865 per share, which is equal to the closing price of Alder’s common stock on October 1, 2018.

The stock option was granted as an inducement material to the employee’s entering into employment with Alder in accordance with Nasdaq Listing Rule 5635(c)(4).

About Alder BioPharmaceuticals, Inc.Alder BioPharmaceuticals is a clinical-stage biopharmaceutical company focused on transforming the migraine treatment paradigm through the discovery, development and commercialization of novel therapeutic antibodies. Alder’s lead product candidate, eptinezumab, is a pivotal-stage monoclonal antibody (mAb) that inhibits calcitonin gene-related peptide (CGRP). Eptinezumab is currently in late-stage clinical development and, if approved, will be the first-to-market infusion therapy for migraine prevention. Alder is also developing ALD1910, a preclinical mAb that inhibits pituitary adenylate cyclase-activating polypeptide-38 (PACAP-38) for migraine prevention. For more information, visit www.alderbio.com.

Investor Relations Contact:                                         Michael SchaffzinStern Investor Relations, [e-mail]

Media Contact: Ashley [e-mail]310.463.0143