Two new experimental treatments for advanced melanoma have shown promise in keeping the deadly skin cancer at bay, according to research presented in the United States on Monday.

The agents, known as Trametinib and Dabrafenib, are being developed by the British pharmaceutical firm GlaxoSmithKline, and were tested in clinical trials against standard chemotherapy treatments.

The trial on Trametinib included 322 people, of whom 214 took the experimental drug while the rest did standard chemotherapy, researchers said at the American Society of Clinical Oncology meeting in Chicago.

More than 22 percent of those on Trametinib responded to treatment compared to 8 percent in the chemo group.

The Trametinib group also experienced a median 4.8 month period in which the cancer did not advance, and saw their risk of dying from skin cancer diminish by 46 percent compared to the chemo group. Eighty-one percent were still alive after six months of treatment compared to 67 percent in the control group.

The phase III trial was the first to evaluate a treatment against melanoma that inhibits a protein known as MEK, and may help about half of all melanoma patients who have a mutation in the BRAF gene that fuels tumor growth.

"This is the first in a new class of targeted drugs that could benefit patients with melanoma who have BRAF mutations," said Caroline Robert, head of Dermatology at the Institute Gustave Roussy in Paris.

"The findings show that targeting the MEK molecular pathway is a viable strategy for treating many people with the disease," Robert added.

"Trametinib is likely to become another first-line treatment option for patients with advanced melanoma."

One other therapy on the market, vemurafenib (Zelboraf), is currently approved in the US and Europe for advanced melanoma.

The second trial involved Dabrafenib, which also targets cancers with the BRAF mutation, and showed a 70 percent lower risk of cancer progression compared to those treated with chemotherapy alone (5.1 months versus 2.7 months).

The phase III trial included 250 participants who had not been treated with any drug prior to enrollment and who had been diagnosed with inoperable melanoma, 187 of whom took the experimental drug while the rest were given standard chemotherapy.

Half of patients in the Dabrafenib group responded to therapy, compared to 6 percent of patients treated with a chemotherapy treatment known as dacarbazine.

The median time in which the cancer did not progress was 5.1 months in the Dabrafenib group compared to 2.7 months in the control group.

More study is needed to determine the overall survival rate, researchers said.

"These findings represent another advance for treating melanoma and form the foundation for further studies to evaluate the role of Dabrafenib in combination with other drugs," said lead investigator Axel Hauschild, a professor of dermatology at the University of Kiel in Germany.

According to the US National Cancer Institute, there are about 76,000 new cases of melanoma diagnosed each year in the US and more than 9,100 deaths.

Agence France-Presse