AIDS drug helps to keep HBV at bay during chemotherapy for breast cancer

Researchers in Hong Kong have discovered a way to help prevent the reactivation of the hepatitis B virus in women who are being treated with chemotherapy for breast cancer.

Dr Winnie Yeo told the 4th European Breast Cancer Conference in Hamburg: “In several developing countries, as many as twelve per cent of breast cancer patients carry the hepatitis B virus. These patients are at risk of developing HBV reactivation during chemotherapy, which is a well-known complication resulting in varying degrees of liver damage that may lead to death.”*

Chemotherapy suppresses the immune system and therefore allows the virus to replicate. Once chemotherapy stops, the immune system recovers and attempts to clear the virus and this causes the biochemical flare-up of hepatitis.

However, Dr Yeo has found that the anti-viral drug lamivudine can reduce the risk of HBV reactivation during and after chemotherapy. Lamivudine was initially used for treating HIV infection in AIDS patients and now is used frequently for treating HBV infection.

Dr Yeo, an associate professor in the Department of Clinical Oncology at the Chinese University of Hong Kong, treated 27 HBV-carrying breast cancer patients with lamivudine before, during and up to eight weeks after chemotherapy. She compared the results with a control group of 41 consecutive patients who had had chemotherapy without lamivudine and compared the incidence of HBV reactivation, hepatitis, severe hepatitis and any consequent disruption to the chemotherapeutic regime.

“We found that lamivudine significantly reduced the incidence of HBV reactivation, and that the incidence of hepatitis from all causes was reduced,” said Dr Yeo.

Only two patients out of the 27 receiving lamivudine suffered HBV reactivation compared with 17 out of 41 in the control group (seven per cent versus 41 per cent); three patients in the study group suffered from hepatitis and two from severe hepatitis (eleven and seven per cent) compared with 27 patients in the control group who developed hepatitis and six who developed severe hepatitis (66 and 15 per cent). Chemotherapy was disrupted in seven (26 per cent) of the study group and in 21 (51 per cent) of the control group.

Patients in both groups were similar, although more patients were being treated with anthracyclines in the lamivudine group (26 out of 27 patients) than in the control group (23 out of 41 patients).

Dr Yeo said: “These results show very clearly that prophylactic lamivudine significantly reduces the incidence of both HBV reactivation and hepatitis. Therefore I propose that breast cancer patients who are hepatitis B carriers should have anti-viral treatment before the start of chemotherapy.”