Press release

Medivir’s fostrox + Lenvima confirm promise of improved outcomes in advanced liver cancer, detailed and mature data presented at ESMO

  • Mature results from Medivir’s phase 1b / 2a open label trial of fostrox + Lenvima® confirm improved outcomes in second-line advanced liver cancer with a median time to progression (TTP) of 10.9 months1 (4.1 – 18.1).
  • The results showed an objective response (ORR) of 24%, and a median duration of response of 7.0 months.
  • Detailed safety update reinforces the ability to combine fostrox and Lenvima long-term, only 1 patient discontinuing fostrox due to adverse events.
  • Medivir’s fostrox (fostroxacitabine bralpamide) is the only orally-administered, liver-targeted inhibitor of DNA replication. Its unique mechanism for the treatment of liver cancer delivers the cell-killing compound selectively to tumor cells locally in the liver while minimizing harm to healthy cells.

Stockholm, Sweden, September 16, 2024 — Medivir AB (Nasdaq Stockholm: MVIR), a pharmaceutical company focused on developing innovative treatments for cancer in areas of high unmet medical need, today presented positive, mature data from its ongoing phase 1b / 2a study of fostroxacitabine bralpamide (fostrox) + Lenvima® in advanced liver cancer (hepatocellular carcinoma/HCC) at the ESMO (European Society of Medical Oncology) Congress in Barcelona, Spain.

Today’s ESMO update, poster number 986P, presented by Dr Hong Jae Chon on Monday September 16, shows promising duration of benefit with 19% of patients continuing treatment for more than a year and the longest running patient remaining on treatment for over 2 years, with sustained partial response. The patients in the study had disease control on fostrox + Lenvima independent if they benefitted from previous line of therapy, showing potential for all second-line patients to benefit from the combination. The safety and tolerability profile continues to be encouraging with no unexpected adverse events. While hematological adverse events were common, they were temporary in nature. Decreases in neutrophil & platelet counts showed a cyclic pattern with recovery before next cycle of treatment, enabling patients to remain on treatment long-term. Importantly, no patient experienced febrile neutropenia or low platelet count with bleeding and there were no fostrox-related serious adverse events.

Results come despite very poor prognosis for most second-line HCC patients today, with just 5 – 10% responding to current standard of care treatment, and a typical TTP of only 3 - 4 months.

Dr. Pia Baumann, Chief Medical Officer at Medivir, said:
- “With three patients still remaining on study treatment, all of whom treated for more than a year, this data-set is now quite mature. At a median follow-up of 10.5 months, fostrox + Lenvima have clearly shown promise of improved outcomes beyond current alternatives for second-line liver cancer patients. Fostrox is designed to only target tumor cells locally in the liver, without harming healthy cells. It is therefore reassuring to see the tolerability profile of fostrox enabling the combination of two highly potent treatments, fostrox + Lenvima, without compromising patient safety. Patients were able to stay on treatment long-term, which evidently contributes to the extended duration of benefit and a median time to progression of 10.9 months, substantially longer than previously seen in second-line liver cancer. It is with reinforced confidence we continue our preparations for the initiation of the planned phase 2b study comparing fostrox + Lenvima with Lenvima alone in a randomized setting to confirm the benefit of the combination.”

Dr Hong Jae Chon, Professor at CHA Bundang Hospital in Korea, and investigator in the fostrox + Lenvima study, commented:
”Treatment outcomes have improved in first-line with the use of immunotherapy combinations, resulting in more patients fit enough to receive second-line treatment. But with no treatments approved in second-line after immunotherapy, there is a significant unmet medical need for new treatments options for these patients. The phase 1b/2a data for fostrox + Lenvima show highly encouraging clinical benefits for patients, indicating that when adding fostrox to Lenvima, efficacy is better than expected from Lenvima alone. It is especially encouraging that in addition to patients experiencing benefit for an extended period of time, patients also responded to the treatment independent of outcome in previous line of therapy. I look forward to evaluating the efficacy of fostrox plus Lenvima in a randomized, controlled trial.”

The data are from Medivir’s ongoing phase 1b/2a open-label, multi-center, dose-escalation and dose-expansion study, evaluating the safety and efficacy of fostrox in combination with Lenvima in patients for whom current first- or second-line treatment has proven ineffective or is not tolerable.

HCC is the most common type of liver cancer, accounting for more than 80% of cases worldwide.2 There are approximately 660,000 patients diagnosed with HCC per year globally and current five-year survival is less than 20 percent3.

Medivir will host a webcast where Dr Chon and Dr Pia Baumann will present the data and answer questions. The webcast will take place Today, September 16, at 13.45 CET, and will be streamed via a link on the website: www.medivir.com/investors/presentations.

The poster and the presentation from the webcast will also be available on Medivir’s website after the presentation.

For additional information, please contact;

Magnus Christensen, CFO, Medivir AB
Telephone: +46 8 5468 3100
E-mail: magnus.christensen@medivir.com


About fostrox
Fostrox is a liver-targeted inhibitor of DNA replication that delivers the cell-killing compound selectively to the tumor while minimizing the harmful effect on normal cells. This is achieved by coupling an active chemotherapy (troxacitabine) with a prodrug tail. This design enables fostrox to be administered orally and travel directly to the liver where the active substance is released locally in the liver. With this unique mechanism, fostrox has the potential to become the first liver-targeted, orally administered drug that can help patients with various types of liver cancer. A phase 1b monotherapy study with fostrox has been completed and a phase 1b/2a combination study in HCC is ongoing where it has shown encouraging anti-cancer efficacy with a good safety and tolerability profile.

About primary liver cancer
Primary liver cancer is the third leading cause of cancer-related deaths worldwide. Hepatocellular carcinoma (HCC) is the most common cancer that arises in the liver and it is the fastest growing cancer in the USA. Although existing therapies for advanced HCC can extend the lives of patients, treatment benefits are insufficient and death rates remain high. There are approximately 660,000 patients diagnosed with primary liver cancer per year globally and current five-year survival is less than 20 percent2,3. HCC is a heterogeneous disease with diverse etiologies, and lacks defining mutations observed in many other cancers. This has contributed to the lack of success of molecularly targeted agents in HCC. The limited overall benefit, taken together with the poor overall prognosis for patients with intermediate and advanced HCC, results in a large unmet medical need.

About Medivir
Medivir develops innovative drugs with a focus on cancer where the unmet medical needs are high. The drug candidates are directed toward indication areas where available therapies are limited or missing and there are great opportunities to offer significant improvements to patients. Medivir is focusing on the development of fostroxacitabine bralpamide (fostrox), a drug candidate designed to selectively treat cancer cells in the liver and to minimize side effects. Collaborations and partnerships are important parts of Medivir’s business model, and the drug development is conducted either by Medivir or in partnership. Medivir’s share (ticker: MVIR) is listed on Nasdaq Stockholm’s Small Cap list. www.medivir.com.

  1. Data cut-off 19 August, 2024
  2. Rumgay et al.,European Journal of Cancer 2022 vol.161, 108-118.
  3. Yang, J.D., Hainaut, P., Gores, G.J. et al. A global view of hepatocellular carcinoma: trends, risk, prevention and management. Nat Rev Gastroenterol Hepatol 16, 589–604 (2019).