Medivir announces TMC435 in an expanded clinical collaboration

  · Expanded clinical study program evaluating a combination of TMC435 and
daclatasvir (BMS-790052)
  · TMC435 and BMS-986094 (formerly INX-189), two
direct-acting antivirals in combination, will be evaluated in clinical
trial

Stockholm, Sweden - Medivir AB (OMX:MVIR), the research-based
speciality pharmaceutical company focused on the development of high-value
treatments for infectious diseases, announces that its development partner,
Janssen R&D Ireland has broadened its clinical collaboration agreement with
Bristol-Myers Squibb Company (NYSE:BMY).

  · This announcement concerns an
expansion of the clinical collaboration agreement between Tibotec
Pharmaceuticals (now Janssen R&D Ireland) and Bristol-Myers Squibb (NYSE:BMY)
announced by Bristol-Myers Squibb on 2nd December 2011
  · Bristol-Myers Squibb
and Janssen have agreed, pending the outcome of the upcoming phase II study, to
further study daclatasvir (BMS-790052) and TMC435 in a phase III trial.
  ·
Bristol-Myers Squibb and Janssen have agreed to conduct a drug-drug interaction
study with TMC435 and BMS-986094. Results from the DDI study will guide the
further evaluation of the use of TMC435 and BMS-986094 in HCV
patients.

TMC435 and daclatasvir (BMS-790052)
In the agreement announced on
2ndDecember 2011, TMC435, a once daily potent NS3/4A protease inhibitor (PI) in
phase III development for the treatment of genotype-1 chronic hepatitis C virus
(HCV) infection will be investigated in a combination in a phase II trial with
Bristol-Myers Squibb´s investigational NS5A replication complex inhibitor,
daclatasvir (BMS-790052), also in phase III development.

In the upcoming
phase II study the companies will evaluate the potential to achieve sustained
viral response 12 and 24 weeks post treatment in null responder and interferon
intolerant patients with HCV genotype 1. This study is planned to start later in
2012.

TMC435 and BMS-986094 (INX-189)
The expanded clinical agreement also
includes clinical evaluation of a combination of TMC435 and the nucleotide
polymerase NS5B inhibitor BMS-986094, formerly known as INX-189. A drug-drug
interaction (DDI) study with TMC435 and BMS-986094 will be conducted. Results
from the DDI study will guide the further evaluation of the use of TMC435 and
BMS-986094 in HCV patients.

Charlotte Edenius, Executive VP Research &
Development, of Medivir commented: “We are very excited to see this expanded
collaboration between Janssen and Bristol-Myers Squibb and to be investigating
TMC435 with the nucleotide BMS-986094 and to expand the clinical collaboration
evaluating TMC435 with daclatasvir. This represents one of several strategies to
explore TMC435 in interferon free regimens; a development we believe will be an
important advancement in the HCV field for patients.”

About TMC435
TMC435 is
a highly potent once-daily (q.d.) investigational drug that is being jointly
developed by Janssen R&D Ireland and Medivir to treat chronic hepatitis C virus
infections in genotype 1 patients.

TMC435 - On-going global phase III program
in brief:

  · TMC435-C208 or QUEST-1 in 375 treatment-naïve genotype-1
patients
  · TMC435-C216 or QUEST-2 in 375 treatment-naïve genotype-1
patients
  · TMC435-C3007 or PROMISE in 375 genotype-1 patients who have
relapsed after prior interferon-based treatment
  · Phase III program in Japan,
includes 417 genotype-1 treatment naïve and treatment experienced patients
  ·
TMC435-C3001 is a phase III efficacy, safety and tolerability study comparing
TMC435 versus telaprevir, each in combination with Pegylated Interferon α-2a
(PegINF) and ribavirin (RBV), in hepatitis C genotype-1 infected patients who
were null or partial responders to prior PegINF/RBV therapy
  · TMC435-C3011 is
an open label, single arm phase III trial to explore the efficacy, safety and
tolerability of TMC435 150 mg once daily, in combination with PegIFN/RBV in 100
treatment naïve or treatment experienced, hepatitis C genotype-4 infected
patients

For additional information from these studies, please see
www.medivir.com and www.clinicaltrials.gov

About Hepatitis C
Hepatitis C is
a blood-borne infectious disease of the liver and is a leading cause of chronic
liver disease and liver transplants. The World Health Organization estimates
that nearly 180 million people worldwide, or approximately 3% of the world's
population, are infected with hepatitis C virus (HCV). The CDC has reported that
almost three million people in the United States are chronically infected with
HCV.

For more information about Medivir, please contact:

Medivir
Mobile: +46 708 537 292 
Rein Piir, EVP Corporate Affairs &
IR
M:Communications
medivir@mcomgroup.com
Europe: Mary-Jane Elliott, Amber Bielecka, Hollie Vile
+44(0)20 7920 2330

About Medivir
Medivir is an emerging research-based
specialty pharmaceutical company focused on the development of high-value
treatments for 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
TMC435, a novel protease inhibitor in phase III clinical development for
hepatitis C that is being developed in collaboration with Janssen
Pharmaceuticals.

In June 2011, Medivir acquired the specialty pharmaceutical
company BioPhausia to ensure timely commercialisation of TMC435 in the Nordic
markets, once approved.

Medivir’s first product, the unique cold sore product
Xerese®/Xerclear®, was launched on the US market in 2011. Xerese®/Xerclear®,
which has been approved in both the US and Europe, is being launched in
collaboration with GlaxoSmithKline to be sold OTC in Europe, Japan and Russia.
Rights in North America, Canada and Mexico were sold to Meda AB in June 2011.
Medivir has retained the Rx rights for Xerclear® in Sweden and Finland.

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