Treximet® acquisition

May 14, 2014

NASDAQ GM: PTX

The following is a slide presentation relating to the proposed transaction described therein that was made available beginning on May 14, 2014

Safe Harbor StatementThe following presentation includes “forward-looking statements” within the meaning of the “safe harbor” provisions of the Private Securities Litigation Reform Act of 1995. You should be aware that our actual results could differ materially from those contained in the forward looking statements, which are based on management’s current expectations and are subject to a number of risks and uncertainties, including, but not limited to, our failure to successfully commercialize our product candidates; costs and delays in the development and/or FDA approval of our product candidates, including as a result of the need to conduct additional studies, or the failure to obtain such approval of our products or product candidates; changes in regulatory standards or the regulatory environment with any of our product candidates; our inability to maintain or enter into, and the risks resulting from our dependence upon, collaboration or contractual arrangements necessary for the development, manufacture, commercialization, marketing, sales and distribution of any products, including our inability to protect our patents or proprietary rights and obtain necessary rights to third party patents and intellectual property to operate our business; our inability to operate our business without infringing the patents and proprietary rights of others; general economic conditions; the failure of any products to gain market acceptance; our inability to obtain any additional required financing; technological changes; changes in industry practice; and one-time events. More detailed information about the Company and the risk factors that may affect the realization of forward-looking statements is set forth in the Company’s filings with the Securities and Exchange Commission. Such documents may be read free of charge on the company’s web site, www.pernixtx.com, or the SEC’s web site at www.sec.gov. You are cautioned not to place undue reliance on these forward-looking statements, which speak only as of the date hereof.

Pernix™ is a registered trademark of Pernix Therapeutics, LLC. Other trademarks referenced herein are the property of their respective owners. ©2014 Pernix Therapeutics Holdings, Inc.

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Acquisition Rationale• Transforms Pernix profitability profile

– Adds immediate revenues and earnings, FY2013 Treximet® net revenues $78.7 million

– Expected to nearly double Pernix revenues and provide EBITDA margins in excess of 30% on a FY2014 pro forma basis

– Pernix estimates pro forma FY2015 total company revenues will exceed $230 million with an EBITDA margin of over 40%

• Expands portfolio of CNS brands – Leverages Pernix existing sales presence and experience

across psychiatry and neurology customers• Enhances Pernix ability to drive continued growth

through future acquisitions

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Transaction Overview• Pernix will make an upfront payment to GSK of

$250 million for the U.S rights to Treximet®

– Represents 3.2x FY2013 sales and 4.5x FY2013 EBITDA*– Pernix will purchase existing inventory from GSK– GSK will continue to manufacture Treximet® under a

long-term Supply Agreement with Pernix– Additional consideration of $17 million payable upon

receipt of updated FDA Written Request for pediatric exclusivity

– Pernix will continue to make royalty payments at 18% of net sales to CPPIB Investments with $4 million quarterly minimum

• Transaction expected to close no later than Aug 1, 2014

• Transaction will be financed through a combination of cash, debt and equity-linked or other securities– Aim to minimize dilution to existing investors

*applying PTX cost structure

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Overview of Treximet®

• Fixed dose combination: sumatriptan / naproxen sodium• Current FDA approval:

– Acute treatment of migraine attacks with or without aura in adults

– Once-daily oral dosing (85mg sumatriptan / 500mg naproxen tablet)

– Second-line therapy for single triptan failure• Differentiated combination migraine treatment -

demonstrated superior efficacy to sumatriptan or naproxen alone in clinical trials– Bilayer tablet developed by POZEN and launched in 2008 by

GSK• Significant revenue growth potential through increased

promotion– Very little promotion of competing products– No sales force promotion of Treximet® since 2012

• 4 Orange Book patents: 3 expire Aug. 2017; 1 expires Oct. 2025– Anticipated pediatric exclusivity to Feb. 2018– Opportunities for further life cycle extension

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Adolescent Migraine Represents a Significant Unmet Need

• Adolescent migraine– 25M adolescents (age 12-17) in U.S.*– Prevalence of adolescent migraine is 10%**– About half of adolescents present to physicians– Treated population is estimated at 30%– Treximet® first sumatriptan for adolescent migraine if approved

• Pernix will complete the filing of a pediatric indication for Treximet® to extend the product’s life

• Limited CMC work to be completed; filing before YE2014• Three studies conducted based on the FDA formal pediatric

request– Adolescent pharmacokinetic study completed late 2009– Adolescent long-term safety study completed April 2010– Adolescent efficacy study completed June 2010

*2012 study by the U.S. Department of Human Health Services**Migraine Research Foundation estimates

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Patents Tested by Generics

• Four challenges were consolidated into one case– Teva settled in April 2010

• Trial against the other 3 defendants was held in October 2010– Sun, Dr. Reddys, Alphapharm– Preliminary injunction issued April 2011– Decision was issued on August 5, 2011

• All three patents in question decided in POZEN’s favor• The Court held that the asserted claims of the 3 POZEN

patents, ‘499 (expires 8/2017) ‘458 (expires 8/2017) and ’183 (expires 10/2025), listed in the Orange Book for Treximet® were:– Valid (not obvious);– Enforceable (no inequitable conduct was committed by

POZEN); and– Infringed by the defendants’ products

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Pernix Core Promoted Brands

CNS Antibiotics Gastroenterology

Specialty Brands Primary Care Brands

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Synergies with Current Portfolio• Current focus on high prescribers of specialized

CNS products– Strong “specialist” PCP prescriber base

• Treximet® faces similar issues– Highly genericized market– Managed care barriers– Generic of active ingredient(s) available

• Unique dose not available in generic

• As well as similar opportunities– Limited promotion by competitors– Strong data to support efficacy– Clear life-cycle plan – Pricing elasticity

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Transforming Pernix• PTX is poised to grow Treximet® revenues

– Highly motivated and successful sales force– Strong overlap of key prescribers with current sales call

plan– Experience in successfully executing pricing and

reimbursement programs– Extensive management team experience in successfully

launching over 75 pharma products• PTX has the financial strength and experience to

close the deal quickly– $50 million cash and up to $40 million potential

available under revolver – Morgan Stanley and Barclays engaged for financing– Management team has successfully executed over 100

pharma deals

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Important safety information about Treximet®

For Full Prescribing Information, please visit www.Treximet.com.Prescription Treximet® is indicated for the acute treatment of migraine attacks, with or without aura, in adults. Treximet® should only be used where a clear diagnosis of migraine headache has been established. Treximet® may cause an increased risk of serious cardiovascular thrombotic events, myocardial infarction, and stroke, which can be fatal. This risk may increase with duration of use. Patients with cardiovascular disease or risk factors for cardiovascular disease may be at greater risk. Treximet® contains a non-steroidal anti-inflammatory drug (NSAID). NSAID-containing products cause an increased risk of serious gastrointestinal adverse events including bleeding, ulceration, and perforation of the stomach or intestines, which can be fatal. These events can occur at any time during use and without warning symptoms. Elderly patients are at greater risk for serious gastrointestinal events. Treximet® is contraindicated in patients with history, symptoms, or signs of ischemic cardiac, cerebrovascular, or peripheral vascular syndromes and in patients with other significant underlying cardiovascular diseases. Treximet® should not be given to patients in whom unrecognized coronary artery disease is predicted by the presence of risk factors without a prior cardiovascular evaluation. Treximet® should not be given to patients with uncontrolled hypertension because the components have been shown to increase blood pressure. Concurrent administration of MAO-A inhibitors or use of Treximet® within two weeks of discontinuation of MAO-A inhibitor therapy is contraindicated. Treximet® and any ergotamine-containing or ergot-type medication (like dihydroergotamine and mthysergide) should not be used within 24 hours of each other. Since Treximet® contains sumatriptan, it should not be administered with another 5-HT1 agonist. 11

Treximet® is contraindicated in patients with hepatic impairment. Treximet® is contraindicated in patients who have had allergic reactions to products containing naproxen. It is also contraindicated in patients in whom aspirin or other NSAIDs/analgesic drugs induce the syndrome of asthma, rhinitis, and nasal polyps. Both types of reactions have the potential of being fatal. Treximet® is contraindicated in patients with hypersensitivity to sumatriptan, naproxen, or any other component of the product. Cerebrovascular events have been reported in patients treated with sumatriptan. In a number of cases, it appears possible that the cerebrovascular events were primary. It is important to advise patients not to administer Treximet® if a headache being experienced is atypical. The development of a potentially life-threatening serotonin syndrome may occur with triptans, including treatment with Treximet®, particularly during combined use with selective serotonin reuptake inhibitors (SSRIs) or selective norepinephrine reuptake inhibitors (SNRIs). NSAID-containing products, including Treximet®, should be prescribed with extreme caution in those with a prior history of ulcer disease or gastrointestinal bleeding. Treximet should not be used in late pregnancy because NSAID-containing products have been shown to cause premature closure of the ductus arteriosus. Treximet® should not be used during early pregnancy unless the potential benefit justifies the potential risk to the fetus.

Important safety information about Treximet®

For Full Prescribing Information, please visit www.Treximet.com.

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