Successful Phase II clinical trial completed with Medivir€s shingles antiviral MIV-606.

Successful Phase II clinical trial completed with Medivir's shingles antiviral MIV-606. A successful phase II-study clinical trial regarding treatment of shingles with MIV-606 has now been completed. The results show that MIV-606 has good antiviral activity and is at least as efficacious as the drug currently most used, acyclovir, but at a significantly lower dose. The good results are entirely in line with Medivir's own expectations. The clinical trial further confirmed that MIV-606 has a good safety profile.The results suggest that there is a relationship between the dose of MIV-606 and the duration of post-herpetic neuralgia (the difficult to treat chronic pain). Larger scale phase III clinical trials are now planned to further validate these promising results. The trial provides Medivir with high quality phase II documentation for the coming clinical trials. "MIV-606 is the first pharmaceutical developed specially for shingles. We are pleasantly surprised that even at this early stage of clinical validation we can already discern a relationship between increased dose and decreased duration of the severe residual pain, which we had not expected to show up in a phase II study", says Professor Bo Öberg. "Passing phase II is a very pleasing step for Medivir. It means that we have increased the value of our project portfolio", says Medivir's CEO Jonas Frick. In the beginning of 1999, Medivir bought out Abbott's rights to the substance in conjunction with Abbott's decision to focus its research in other areas. The phase II clinical trial was funded and executed by Abbott, whose future involvement in MIV-606 is limited to a minor portion of future royalty income. Clinical trial design The phase II trials with MIV-606, comprising a randomised, double blind study totalling 153 patients, commenced in June 1998 at a number of centres in USA and Europé. The patients were to be at least 50 years old and treated within 72 hours of lesion development. Patients were treated with the following alternatives: * MIV-606 250 mg twice per day (daily dose 500 mg) * MIV-606 500 mg twice per day (daily dose 1000 mg) * MIV-606 750 mg twice per day (daily dose 1500 mg) * Acyclovir 800 mg five times per day (daily dose 4000 mg) The clinical trial indicated that all doses of MIV-606 were therapeutically efficacious. MIV-606 at a daily dose of 1000-1500 mg was shown to be at least as effective as 4000 mg of acyclovir. The trial further suggests that there is a relationship between the dose of MIV-606 and the duration of post-herpetic neuralgia, the difficult to treat chronic pain. However, this has to be confirmed in larger scale phase III trials. Shingles causes severe pain Around 95% of the population bear the virus which can cause shingles. In the initial infection varicella zoster virus (VZV) causes chicken pox. After the chicken pox infection, VZV remains latent (inactive) in certain of the body's nerve cells. In around 50% of these individuals, VZV will reactivate later in life and cause shingles. Amongst other symptoms, shingles manifests itself as blisters which develop into open lesions. These lesions heal after a couple of weeks, although the viral replication in the nerve tissue with attendant nerve damage can, in many people, cause severe and protracted pain. This pain can be severely handicapping and is very difficult to treat. The risk of contracting shingles increases with age, as does the risk of suffering from post-herpetic neuralgia. The majority of patients over 60 years of age experience post-herpetic neuralgia. Half of all patients over 70 years still experience pain a year later. Virus in the shingles lesions is inactivated by the body's immune system within a few days. Early treatment with, for example, acyclovir can speed up the process, but only to a limited extent. Acyclovir's activity with regard to lesion healing does not appear to be dose-dependent, meaning that increased dose does not seem to additionally speed up healing. Early treatment of shingles patients with acyclovir does somewhat shorten the duration of post herpetic neuralgia. In contrast to this drug's activity on lesion healing, the activity on post herpetic neuralgia seems to be dose-dependent. However, it is not feasible to significantly increase the current dosage regime for acyclovir as the side effects would be too severe. It is likely that a pharmaceutical displaying the superior antiviral activity of MIV-606 ought to further shorten the duration of post herpetic neuralgia. Previous preclinical experience has shown MIV-606 to be more than 40 times more active against VZV than acyclovir. "MIV-606 is furthermore significantly easier for the patient to take - one small tablet twice per day instead of the much bigger tablet five times per day with acyclovir treatment", says Assoc. Prof. Johan Harmenberg, Medivir's Vice President, Clinical Development. There are today no satisfactory shingles drugs Treatment of shingles with current pharmaceuticals is unsatisfactory, especially in relation to reducing post herpetic neuralgia. Additionally, existing drugs have weak activity against VZV and were principally developed for genital herpes rather than shingles. Sales of pharmaceuticals against shingles amounted to around US$ 600 million in 1999. The principal shingles drug today is acyclovir. An efficacious shingles drug should significantly increase the patient treatment rate and therefore also the market size. There do not appear to be any other promising shingles drugs in development aside from MIV-606. Medivir plans for rapid outlicensing Medivir intends to outlicense MIV-606 this year. Sufficient quantities of substance are already manufactured to enable phase III clinical trials. A tablet dosage form has been developed. MIV-606 is protected by strong patents to 2017. Huddinge 25 January 2000 Medivir AB (publ.) For further information please contact: Anna Bernsten, Vice President Business Development and Investor Relations, Medivir AB, phone +46 8 608 31 05, +46 709-369 069 or e-mail anna.bernsten@medivir.se. Information about Medivir on internet: www.medivir.se Medivir is a research and development company which develops new and better substances for the treatment of infectious diseases. The subsidiary company CCS AB develops, manufactures and markets body-care products and pharmaceuticals. The Group consists of the parent company, Medivir AB, the CCS AB subsidiary and UK company CCS (UK) Ltd. ------------------------------------------------------------ Please visit http://www.bit.se for further information The following files are available for download: http://www.bit.se/bitonline/2000/01/25/20000125BIT00190/bit0001.doc http://www.bit.se/bitonline/2000/01/25/20000125BIT00190/bit0002.pdf