$INSY Commences Dosing in Phase 1/2 Safety and Pharmacokinetic Study

The clinical trial will evaluate multiple ascending doses of Insys’ pharmaceutical cannabidiol (CBD) oral solution at three different dosage strengths. The trial is being conducted at multiple study centers across the U.S.

“Rapid advancement of our pharmaceutical CBD program is a key priority for Insys; this first in patient dosing with our pharmaceutical CBD formulation is a significant milestone,” said Michael L. Babich, President and Chief Executive Officer.

“Per the FDA’s request, our PK study is being conducted in epilepsy patients. This will enable us to gain early insight on the safety and tolerability of our CBD candidate in epileptic children who have treatment resistant seizures. We look forward to moving this study forward with the potential to provide significant medical benefits to those suffering this debilitating condition.”

In addition to the ongoing Phase 1/2 study, the Company’s CBD clinical development program includes Phase 3 clinical trials to evaluate the safety and efficacy of its CBD candidate for the treatment of Lennox-Gastaut syndrome and Dravet syndrome, two rare forms of pediatric epilepsy for which Insys’ pharmaceutical CBD formulation has received orphan drug designation. The FDA granted Fast Track designation to Insys’ pharmaceutical CBD formulation for the treatment of Dravet syndrome earlier this year.

Insys expects that its new, DEA-inspected facility in Round Rock, Texas, will enable it to manufacture ample quantities of CBD for its research and commercial plans.

About Pharmaceutical CBD
Cannabidiol (CBD) is one of at least 60 active cannabinoids identified in cannabis. CBD is considered to have a wider scope of medical applications than tetrahydrocannabinol (THC), and appears to have anti-convulsive action in animal models.

Insys’ pharmaceutical CBD is over 99.5% pure cannabidiol. It is synthesized to be chemically identical to the CBD extracted from cannabis, and is produced in a controlled environment. The FDA issued a Drug Master File (DMF) to Insys for its CBD active pharmaceutical ingredient in May 2014.

About Dravet Syndrome
Dravet syndrome, also known as Severe Myoclonic Epilepsy of Infancy, is a rare and catastrophic form of intractable epilepsy that begins in infancy. Initial seizures are most often prolonged events and in the second year of life other seizure types begin to emerge. Development remains on track initially, with plateaus and a progressive decline typically beginning in the second year of life. Individuals with Dravet syndrome face a higher incidence of SUDEP (sudden unexplained death in epilepsy) and have associated conditions, which also need to be properly treated and managed.

About Lennox-Gastaut Syndrome
Lennox-Gastaut syndrome is a severe form of childhood-onset epilepsy that typically manifests between two and six years of age. The syndrome is characterized by multiple seizure types, moderate to severe cognitive impairment, and an abnormal EEG. The frequency and severity of seizures vary by individual. It is often treated with, but has proved resistant to, various anti-seizure medications. There is no cure for the syndrome at this time.

About Insys Therapeutics, Inc.
Insys Therapeutics is a specialty pharmaceutical company that develops and commercializes innovative drugs and novel drug delivery systems of therapeutic molecules that improve the quality of life of patients. Using our proprietary sublingual spray technology and our capability to develop pharmaceutical cannabinoids, Insys addresses the clinical shortcomings of existing commercial products. Insys currently markets two products, Subsys^®, which is sublingual Fentanyl spray for breakthrough cancer pain, and a generic version of Dronabinol (THC) capsules. Our lead product candidate is Dronabinol Oral Solution, a proprietary orally administered liquid formulation of dronabinol. Insys is also developing a pipeline of sublingual sprays, as well as pharmaceutical cannabidiol.

Forward-Looking Statements
This press release contains forward-looking statements, including statements regarding our expectations related to our plan to pursue the development of treatments for Lennox-Gastaut syndrome and Dravet syndrome related to epilepsy, our expectations related to the timelines our pharmaceutical cannabidiol (CBD) candidate, the potential benefits of our pharmaceutical CBD therapies to patients and our expectations in connection with our manufacturing capabilities with respect to our DEA-inspected facility in Round Rock, Texas. These forward-looking statements are based on management’s expectations and assumptions as of the date of this press release, and actual results may differ materially from those in these forward-looking statements as a result of various factors, many of which are beyond our control. For a description of these risks facing the company, please see the risk factors described in our filings with the United States Securities and Exchange Commission, including those factors discussed under the caption “Risk Factors” in our Annual Report on Form 10-K for the year ended December 31, 2014, and any subsequent updates that may occur in our Quarterly Reports on Form 10-Q. Forward-looking statements speak only as of the date of this press release and we undertake no obligation to update or revise these statements, except as may be required by law.