Primary efficacy and safety data from four phase III Japanese studies of Simeprevir presented at The Japan Society of Hepatology

Stockholm, Sweden — Medivir AB (OMX: MVIR) reports that its partner Janssen
Pharmaceutical R&D Ireland (Janssen) today announced primary efficacy and safety
results from four Japanese phase III clinical studies demonstrating that the use
of the investigational NS3/4A protease inhibitor simeprevir (TMC435) led to
sustained virologic response 12 weeks after the end of treatment (SVR12) in
patients with genotype 1 hepatitis C, when administered once daily with
pegylated interferon and ribavirin. The four studies examined the use of
simeprevir in genotype 1 chronic hepatitis C patients who were treatment naïve,
as well as patients who were non-responders to prior therapy or relapsed
following treatment with pegylated interferon with or without ribavirin.

The data were presented today at The Japan Society of Hepatology’s 49th Annual
Meeting in Tokyo. The CONCERTO studies supported the new drug application for
simeprevir, which was submitted to Japanese regulatory authorities in February
2013.

Janssen’s phase III clinical program for simeprevir in Japan consists of four
studies in patients with genotype 1 HCV: CONCERTO-1 in treatment-naïve patients,
CONCERTO-2 and -3 in prior non-responders or patients who relapsed after prior
interferon-based treatment, and CONCERTO-4 using different pegylated interferon
treatments (pegylated interferon alfa-2b) in a broad patient population.

More information about the study design could be found at
www.clinicaltrials.gov.

+--------+----------+---------------------+------------------+
|                          SVR12 in                          |
|                            the                             |
|                          CONCERTO                          |
|                           Trials                           |
+--------+----------+---------------------+------------------+
| Trial  | Patient  |Treatment + pegylated|  Proportion of   |
|        |   Type   |   interferon and    |Patients Achieving|
|        |          |      ribavirin      |    SVR12 (%)     |
+--------+----------+---------------------+------------------+
|CONCERTO|Treatment |Simeprevir (12 weeks)|        89        |
|   -1   |  -naïve  |                     |                  |
+--------+----------+---------------------+------------------+
|        |          | Placebo (12 weeks)  |        62        |
+--------+----------+---------------------+------------------+
|CONCERTO|Prior Non |Simeprevir (12 weeks)|        53        |
|   -2   |-responder|                     |                  |
|        |          |                     |                  |
+--------+----------+---------------------+------------------+
|        |          |Simeprevir (24 weeks)|        36        |
+--------+----------+---------------------+------------------+
|CONCERTO|  Prior   |Simeprevir (12 weeks)|        96        |
|   -3   | Relapser |                     |                  |
+--------+----------+---------------------+------------------+
|CONCERTO|Treatment |Simeprevir (12 weeks)|        92        |
|   -4   |  -naïve  |                     |                  |
+--------+----------+---------------------+------------------+
|        |  Prior   |Simeprevir (12 weeks)|       100        |
|        | Relapser |                     |                  |
+--------+----------+---------------------+------------------+
|        |Prior Non |Simeprevir (12 weeks)|        39        |
|        |-responder|                     |                  |
|        |          |                     |                  |
+--------+----------+---------------------+------------------+

The most common adverse events seen in patients receiving simeprevir plus
pegylated interferon and ribavirin in CONCERTO-1 were similar to those observed
with pegylated interferon and ribavirin alone and were also similar in the other
studies (decreased white blood cell count, fever, anemia, decreased neutrophil
count, malaise, headache and rash). Treatment discontinuation rates due to an
adverse event in CONCERTO-1 were five percent in the simeprevir arm and 8
percent in the placebo arm, four percent in CONCERTO-2, four percent in CONCERTO
-3 and one percent in CONCERTO-4.

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

About Simeprevir
Simeprevir is a new generation NS3/4A protease inhibitor jointly developed by
Medivir and Janssen for the treatment of chronic hepatitis C in adult patients
with compensated liver disease.

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 about 350,000 people per
year die from the disease.

About Medivir
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

Medivir is a collaborative and agile pharmaceutical company with an R&D focus on
infectious diseases and a leading position in hepatitis C. We are passionate and
uncompromising in our mission to develop and commercialize innovative
pharmaceuticals that improve people’s lives.