SUPERNUS PHARMACEUTICALS INC (SUPN) SPO

We estimate that the net proceeds from the sale of common stock that we are
offering will be approximately $44.7 million. This projection is based upon a
public offering price of $8.00 per share, and after deducting underwriting
discounts and commissions as well as estimated offering expenses payable by us.

We anticipate that we will use the net proceeds as follows:

        º approximately $23.0 million for sales and marketing expenses to
          provide continued support of the commercial launch of Oxtellar XR and,
          after approval by the FDA, Trokendi XR;

        º approximately $4.0 million for the manufacture and supply of
          commercial quantities of Oxtellar XR and Trokendi XR inventory to be
          sold in connection with such commercial launch;

        º approximately $3.5 million to fund the continued clinical development
          of SPN-810, including: preclinical carcinogenicity testing; process
          development and scale up for commercial bulk active pharmaceutical
          ingredient;

        º approximately $2.5 million to fund the continued clinical development
          of SPN-812, including preclinical carcinogenicity testing, process
          development for commercial bulk active pharmaceutical ingredient,
          continued Phase II testing and formulation development;

        º approximately $3.0 million to fund Phase IV studies, and
          post-marketing formulation development and clinical work for Oxtellar
          XR and Trokendi XR;

        º approximately $4.5 million to fund our payment obligations under the
          term loans under our secured credit facility; and

        º the remainder, if any, for general corporate purposes including
          general and administrative expenses, capital expenditures and working
          capital.

We believe that net proceeds from this offering will be sufficient to fund the
expected commercial launch of Oxtellar XR in the first quarter of 2013, to
obtain the final FDA approval for Trokendi XR and to fund the expected
commercial launch of Trokendi XR in the third quarter of 2013. In addition, our
operating plan, including our planned commercialization of Oxtellar XR and
Trokendi XR, may change as a result of many factors.

As of September 30, 2012, we had $26.0 million of term loans outstanding under
our secured credit facility, of which $11.9 million mature in August 2014 and
$14.1 million mature in January 2015. The term loans bear interest at a fixed
rate per annum of 11.0%. We used the proceeds of the term loans to fund ongoing
clinical trials for Oxtellar XR, Trokendi XR and SPN-810, to prepare for
manufacturing validation of Oxtellar XR and Trokendi XR, to support formulation
for various clinical stage products, to prepare commercial marketing of Trokendi
XR and for regulatory filing fees.

Although we currently anticipate that we will use the net proceeds as described
above, there may be circumstances where a reallocation of funds may be
necessary. The amounts and timing of our actual expenditures will depend upon
numerous factors, including the progress of our development and
commercialization efforts, the progress of our clinical trials, whether or not
we enter into strategic collaborations or partnerships and our operating costs
and expenditures. Accordingly, our management will have significant flexibility
in applying these net proceeds.

The costs and timing of drug development and commercialization and of regulatory
approval, particularly conducting clinical studies, are highly uncertain, are
subject to substantial risks and can often change. Accordingly, we may change
the allocation of use of these proceeds as a result of contingencies such as the
progress of research, progress of clinical trials, ability to secure approval of
our products from the FDA, uptake of our products in the marketplace and
competitive responses.

Pending use of the proceeds from this offering as described above or otherwise,
we intend to invest the net proceeds in short-term, interest-bearing,
investment-grade securities.

The biotechnology and pharmaceutical industries are highly competitive. A number
of multinational pharmaceutical companies as well as large biotechnology
companies are pursuing the development of or are currently marketing
pharmaceutical products in the anti-epilepsy and ADHD markets on which we are
focusing.

Epilepsy

There are currently over 15 branded products, as well as their generic
counterparts, on the U.S. market indicated to treat some form of epilepsy.
Several NCEs are expected to enter the epilepsy market in the next few years.
Based on IMS Health prescription data from 1994 to 2005 for NCE launches for
seizure disorders, such NCEs, on average, experienced slow market penetration
characterized by a 0.58% to 1.1% market share point gain on an annual basis. We
believe this is because physicians are often reluctant to change a stable
patient's existing therapy and risk a breakthrough seizure in their patients. If
final approval is received, Trokendi XR (extended release topiramate) will
compete with all immediate release topiramate products including Topamax and
related generic products. We are aware that Upsher-Smith announced the
initiation of a Phase III clinical trial for an extended release topiramate
product, which it has described as an internally developed program for the
management of epilepsy in adults using its proprietary formulation technology.
If this product candidate is approved by the FDA before Trokendi XR, then
Upsher-Smith could obtain three years of marketing exclusivity, which would
significantly delay our entry into the U.S. market.

Oxtellar XR (extended release oxcarbazepine) will compete with all immediate
release oxcarbazepine products including Trileptal and related generic products.
We are not aware of any other company that is currently developing an extended
release oxcarbazepine anti-epileptic product in the United States. In addition,
we believe that Oxtellar XR's once-daily formulation solves a drug delivery
challenge specific to oxcarbazepine that must be overcome by all potential
competitors. We are aware of companies who have modified-release oxcarbazepine
products that are marketed outside of the United States but, to our knowledge,
such products are not being pursued for the U.S. market. These modified-release
oxcarbazepine products include Apydan, which is developed by Desitin
Arzneimittel GmbH and requires twice-daily administration.

ADHD

Competition in the U.S. ADHD market has increased with the commercial launch of
several products in recent years, including the launch of generic versions of
branded drugs, such as Adderall XR. Shire plc is one of the leaders in the U.S.
ADHD market with three products: Adderall XR, an extended release stimulant
treatment designed to provide once-daily dosing; Vyvanse, a stimulant prodrug
product launched in 2007; and Intuniv, a non-stimulant treatment launched in
November 2009. Other stimulant products for the treatment of ADHD in the U.S.
market include the following once-daily formulations: Concerta; Metadate CD;
Ritalin LA; Focalin XR; and Daytrana. Other non-stimulants are Strattera and
Kapvay. We are also aware of clinical development efforts by several large
pharmaceutical companies including Shire plc, GlaxoSmithKline plc, Eisai Inc.,
AstraZeneca plc and Abbott Laboratories to develop additional treatment options
for ADHD.