Ganaxolone in PCDH19 Female Pediatric Epilepsy

        We are also developing ganaxolone as a treatment for PCDH19 female pediatric epilepsy, a disorder in which a mutation of the PCDH19 gene causes deficits in GABAergic signaling. Although formal epidemiologic data is not available, results from diagnostic screenings indicate that approximately 10% of girls who have seizure onset before five years of age have PCDH19 mutations. We estimate the PCDH19 population to be approximately 15,000 to 30,000 patients in the United States. These patients typically experience clusters of seizures that can last from one day to weeks. Many of these patients will experience developmental delay, intellectual disability and behavioral problems. We believe that ganaxolone may be useful in treating patients with PCDH19 female pediatric epilepsy because it is a positive allosteric modulator of GABA _A receptors and because of its safety profile and its availability in a liquid suspension and oral capsule form. We are initiating an expanded access protocol in approximately ten patients with PCDH19 female pediatric epilepsy under our epilepsy IND in the second half of 2014. This trial will provide proof-of-concept data, which we anticipate receiving in the first half of 2015.

Additional Indications

        Due to its mechanism of action, we believe ganaxolone may have potential in a variety of neurologic and psychiatric disorders beyond our current clinical focus; however, we will need to undertake additional clinical studies in order to obtain additional labeled indications. Potential additional indications include generalized anxiety disorder, posttraumatic stress disorder and depression, multiple sclerosis, addictive behaviors such as alcoholism and smoking, attention deficit hyperactivity disorder, or ADHD, and orphan disorders such as Super Refractory Status Epilepticus, or SRSE, Neimann Pick Disease, Type C and certain autism subtypes. If we decide to pursue any additional indications for ganaxolone, we would need to undertake additional clinical trials.

Ganaxolone Safety and Tolerability

        In Phase 1 and 2 clinical trials, ganaxolone has been administered in approximately 1,000 subjects at therapeutically relevant dose levels and treatment regimens for up to two years. In these clinical trials, ganaxolone was generally well tolerated with no adverse effects on cardiovascular, liver, blood or other systems. In animal studies there was no evidence of reproductive toxicity or other toxicities after long-term administration of ganaxolone.

Our Strategy

        Our goal is to maximize the value of ganaxolone as a first-in-class innovative neuropsychiatric therapy with a portfolio of diversified indications. The key elements of our strategy to achieve this goal include:

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executing our registration studies and pursue regulatory approval for ganaxolone for adjunctive treatment of focal onset seizures and other epilepsy indications;



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expanding indications for ganaxolone, including use in pediatric seizure disorders;



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commercializing ganaxolone in the United States either alone or in collaboration with others; and



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establishing collaborations to develop and commercialize ganaxolone in territories outside the United States.

Risk Factors

        Our ability to implement our business strategy is subject to numerous risks and uncertainties. As a clinical stage biopharmaceutical company, we face many risks inherent in our business and our industry generally. You should carefully consider all of the information set forth in this prospectus and, in

 

particular, the information under the heading "Risk Factors" in this prospectus prior to making an investment in our common stock. These risks include, among others, the following:

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We have a limited operating history, have incurred significant losses since our inception and anticipate that we will continue to incur losses in the future.



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We have not generated any revenue to date from product sales. We may never achieve or sustain profitability, which could depress the market price of our common stock, and could cause you to lose all or a part of your investment.



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We will require additional capital to fund our operations and if we fail to obtain necessary financing, we may be unable to complete the development and commercialization of ganaxolone.



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Our future success is dependent on the successful clinical development, regulatory approval and commercialization of ganaxolone, which is currently undergoing two clinical trials and will require significant capital resources and years of additional clinical development effort.



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Our commercial success depends upon attaining significant market acceptance of ganaxolone, if approved, among physicians, patients, government and private payors and others in the medical community.



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We rely on third parties to conduct our preclinical studies and clinical trials. If these third parties do not successfully carry out their contractual duties or meet expected deadlines, we may not be able to obtain regulatory approval for or commercialize ganaxolone.



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Government funding for certain of our programs adds uncertainty to our research efforts with respect to those programs and may impose requirements that increase the costs of commercialization and production of product candidates developed under those government-funded programs.



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If we are unable to protect our intellectual property rights or if our intellectual property rights are inadequate for our technology and product candidates, our competitive position could be harmed.



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Our future success depends on our ability to retain our executive officers and to attract, retain and motivate qualified personnel.

Corporate Information

        We were incorporated in Delaware in August 2003. Our principal executive offices are located at 142 Temple St., Suite 205, New Haven, Connecticut 06510 and our telephone number is (203) 315-0566. Our website address is www.marinuspharma.com . The inclusion of our website address in this prospectus is, in each case, intended to be an inactive textual reference only and not an active hyperlink to our website. The information contained in, or that can be accessed through, our website is not part of this prospectus.

Implications of Being an Emerging Growth Company

        We are an "emerging growth company," as defined in Section 2(a) of the Securities Act of 1933, as amended, or the Securities Act, as modified by the Jumpstart Our Business Startups Act of 2012, or the JOBS Act. As such, we are eligible to take advantage of exemptions from various disclosure and reporting requirements that are applicable to other public companies that are not "emerging growth companies" including, but not limited to:

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not being required to comply with the auditor attestation requirements of Section 404(b) of the Sarbanes-Oxley Act of 2002, or the Sarbanes-Oxley Act;

 

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being permitted to present only two years of audited financial statements and only two years of related Management's Discussion and Analysis of Financial Condition and Results of Operations, in each case, instead of three years;



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being permitted to present the same number of years of selected financial data as the years of audited financial statements presented, instead of five years;



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reduced disclosure obligations regarding executive compensation, including the omission of a compensation disclosure and analysis;



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not being required to comply with any requirement that may be adopted by the Public Company Accounting Oversight Board regarding mandatory audit firm rotation or a supplement to the auditor's report providing additional information about the audit and the financial statements; and



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exemptions from the requirements of holding a non-binding advisory vote on executive compensation and stockholder approval of any golden parachute payments not previously approved.

        We may choose to take advantage of some or all of the available exemptions. We have taken advantage of some of the reduced reporting burdens in this prospectus. Accordingly, the scope of the information contained herein may be different than the scope of the information you receive from other public companies in which you hold stock. We do not know if some investors will find our shares less attractive as a result of our utilization of these or other exemptions. The result may be a less active trading market for our shares, and our share price may be more volatile.

        In addition, Section 107 of the JOBS Act also provides that an "emerging growth company" can take advantage of the extended transition period provided in Section 7(a)(2)(B) of the Securities Act for complying with new or revised accounting standards. In other words, an "emerging growth company" can delay the adoption of certain accounting standards until those standards would otherwise apply to private companies. We have irrevocably elected not to avail ourselves of this exemption from new or revised accounting standards and, therefore, we will be subject to the same new or revised accounting standards as other public companies that are not emerging growth companies.

        We will remain an "emerging growth company" until the earliest of (a) the last day of the first fiscal year in which our annual gross revenues exceed $1.0 billion; (b) the date that we become a "large accelerated filer" as defined in Rule 12b-2 under the Securities Exchange Act of 1934, as amended, or the Exchange Act, which would occur if the market value of our shares that are held by non-affiliates exceeds $700 million as of the last business day of our most recently completed second fiscal quarter; (c) the date on which we have issued more than $1.0 billion in nonconvertible debt during the preceding three-year period; and (d) the last day of our fiscal year containing the fifth anniversary of the date on which shares of our common stock become publicly traded in the United States.