New data from Simeprevir phase III studies Quest 1 and 2 in hepatitis C patients will be presented at EASL 23-28 April in Amsterdam

Stockholm, Sweden — Medivir AB (OMX: MVIR) today announces that data will be
presented on the investigational protease inhibitor simeprevir (TMC435) for the
treatment of genotype 1 hepatitis C patients.

These primary efficacy and safety results from two global phase III studies
demonstrate that use of the investigational protease inhibitor simeprevir led to
sustained virologic response 12 weeks after the end of treatment (SVR12) in 80
and 81 percent, respectively, of treatment-naïve genotype 1 chronic hepatitis C
adult patients with compensated liver disease, when administered once daily with
pegylated interferon and ribavirin. In both studies, 50 percent of patients
receiving pegylated interferon and ribavirin alone achieved SVR12.

The data will be presented this week at The International Liver Congress 2013 of
the European Association for the Study of the Liver (EASL) in Amsterdam, The
Netherlands. The QUEST-1 and QUEST-2 data will also be discussed in an official
EASL press conference on April 24 at 11:00 a.m. CEST.

"We are very happy about the robust high cure rates and the very good safety
profile of simeprevir as demonstrated in the QUEST 1 and 2 studies both also
including patients with severe liver disease and other characteristics that are
predictors of more difficult to cure patients”, said Charlotte Edenius, EVP
Development, Medivir AB. “ These data together with the data from a third phase
III study in relapser patients (PROMISE study) form the basis for the regulatory
filings which were recently submitted in both Japan and US while the EU
submission is expected in the near future."

In QUEST-1 and QUEST-2, patients were randomized to receive simeprevir or
placebo for 12 weeks plus pegylated interferon and ribavirin for 24 or 36 weeks.
In findings related to a secondary endpoint, 85 (QUEST-1) and 91 percent (QUEST
-2) of patients receiving simeprevir were able to shorten therapy with pegylated
interferon and ribavirin to 24 weeks due to meeting response-guided therapy
(RGT) criteria.
Of those patients meeting RGT criteria to stop treatment at 24 weeks, 91 percent
(QUEST-1) and 86 percent of patients (QUEST-2) achieved SVR12.

“These data represent new and important improvements infor the future treatment
of genotype 1 hepatitis C patients”, said Maris Hartmanis, Medivir’s CEO.

Patients enrolled in QUEST-1 and QUEST-2 were stratified by HCV genotype 1
subtype and IL28B genotype. In QUEST-1, among patients treated with simeprevir,
SVR12 rates according to IL28B genotype were 94 percent (CC), 76 percent (CT),
and 65 percent (TT). In QUEST-2, in the simeprevir arm, SVR12 rates according to
IL28B genotype were 96 percent (CC), 80 percent (CT), and 58 percent (TT). Among
patients with METAVIR scores F3 and F4, 70 percent of patients treated with
simeprevir in QUEST-1 and 66 percent of patients treated with simeprevir in
QUEST-2 achieved SVR12. Among patients with METAVIR scores F0 to F2, 83 percent
of patients treated with simeprevir in QUEST-1 and 85 percent of patients
treated with simeprevir in QUEST-2 achieved SVR12. The METAVIR score is used to
quantify the degree of inflammation and fibrosis of the liver and patients are
scored on a four-point scale.

The most common adverse events seen in patients receiving simeprevir in QUEST-1
were fatigue (42 percent versus 41 percent for placebo), itch (26 percent versus
16 percent for placebo), and headache (33 percent versus 39 percent for
placebo). The most common adverse events seen in patients receiving simeprevir
in QUEST-2 were fatigue (37 percent versus 42 percent for placebo), itch (25
percent versus 25 percent for placebo), headache (39 percent versus 37 percent
for placebo), fever (31 percent versus 40 percent for placebo), and influenza
-like illness (26 percent versus 26 percent for placebo). In QUEST-1, in both
the simeprevir and placebo arms, 3 percent of patients discontinued treatment
due to an adverse event. In QUEST-2, 2 percent of patients in the simeprevir arm
and 1 percent of patients in the placebo arm discontinued treatment due to an
adverse event.

About QUEST-1 and QUEST-2
QUEST-1 and QUEST-2 are global, phase III, randomized, double-blind, placebo
controlled clinical trials assessing the efficacy, safety and tolerability of
simeprevir plus pegylated interferon and ribavirin versus pegylated interferon
and ribavirin alone in treatment-naïve adult patients with genotype 1 chronic
hepatitis C with compensated liver disease.

In the QUEST-1 and QUEST-2 trials, 394 and 391 patients, respectively, were
randomized to receive one 150 mg capsule of simeprevir or placebo once daily
plus pegylated interferon and ribavirin for 12 weeks, followed by pegylated
interferon and ribavirin alone for either 12 or 36 weeks based on RGT criteria.
Patients in the simeprevir arm were considered to have met RGT criteria if their
HCV RNA levels were

For more information please contact:
Rein Piir, EVP Corporate Affairs & IR
Mobile: +46 708 537 292.

About Simeprevir
Simeprevir is an investigational NS3/4A protease inhibitor jointly developed by
Janssen and Medivir AB for the treatment of genotype 1 chronic hepatitis C in
adult patients with compensated liver disease. Janssen recently announced the
submission of new drug applications for simeprevir in Japan and the United
States for the treatment of genotype 1 hepatitis C.

Global phase III studies of simeprevir include QUEST-1 and QUEST-2 in treatment
-naïve patients, PROMISE in patients who have relapsed after prior interferon
-based treatment and ATTAIN in null-responder patients. In parallel to these
trials, phase III studies for simeprevir are ongoing in treatment-naïve and
treatment-experienced HIV-HCV co-infected patients and HCV genotype 4 patients.

Simeprevir is also being studied in phase II interferon-free trials with and
without ribavirin in combination with:

  · Janssen’s non-nucleoside inhibitor TMC647055 and ritonavir in treatment
-naïve genotype 1a and 1b HCV patients;

  · Gilead Sciences, Inc.’s nucleotide inhibitor sofosbuvir (GS-7977) in
treatment-naïve and previous null-responder genotype 1 HCV patients; and
  · Bristol-Myers Squibb's NS5A replication complex inhibitor daclatasvir (BMS
-790052) in treatment-naive and previous null-responder genotype 1 HCV patients.

In addition, Janssen has entered into a non-exclusive collaboration with Vertex
Pharmaceuticals to evaluate in a phase II study the safety and efficacy of an
all-oral regimen of simeprevir and Vertex’s investigational nucleotide analogue
polymerase inhibitor VX-135 for the treatment of HCV. As a first step, Janssen
Pharmaceutical Inc. will conduct a drug-drug interaction (DDI) study with
simeprevir and VX-135.

Janssen also has plans to initiate a phase II trial of an investigational
interferon-free regimen with simeprevir, TMC647055 and Idenix’s IDX719, a once
-daily, pan-genotypic NS5A inhibitor, with and without ribavirin.

For additional information about simeprevir clinical trials, please visit
www.clinicaltrials.gov.

About Hepatitis C
Hepatitis C, a blood-borne infectious disease of the liver and a leading cause
of chronic liver disease and liver transplants, is a rapidly evolving treatment
area with a clear need for innovative treatments. Approximately 150 million
people are infected with hepatitis C worldwide, and 350,000 people per year die
from the disease.

About Medivir AB
Medivir is an emerging research-based pharmaceutical company focused on
infectious diseases.
Medivir has world class expertise in polymerase and protease drug targets and
drug development which has resulted in a strong infectious disease R&D
portfolio. The Company’s key pipeline asset is simeprevir, a novel protease
inhibitor in late phase III clinical development for hepatitis C that is being
developed in collaboration with Janssen R&D Ireland. Medivir has also a broad
product portfolio with prescription pharmaceuticals in the Nordics.

For more information about Medivir AB, please visit the Company’s website:
www.medivir.com