UPDATE 1-Sanofi and Merck KGaA team up to test cancer drugs

* Testing experimental drugs in combination is new trend

* AstraZeneca, U.S. Merck clinched first such tie-up in 2009

* Goal is to disrupt multiple pathways driving tumour growth

(Adds context on similar deals, quote, previous PARIS)

By Ben Hirschler

LONDON, Dec 17 (Reuters) - Sanofi-Aventis (SASY.PA) and Merck KGaA (MRCG.DE) are teaming up to test new cancer drugs in combination, joining a trend among drugmakers to combine different cancer therapies in early-stage clinical studies.

Combination drug treatments are not uncommon in cancer, but such regimens are normally developed only after medicines reach late-stage testing or are already on the market.

Now that is starting to change.

AstraZeneca (AZN.L) and Merck & Co (MRK.N) led the way last year with the first such agreement to study two experimental cancer drugs with different mechanisms of action, and GlaxoSmithKline (GSK.L) and Novartis (NOVN.VX) announced a similar tie-up earlier this year.

In all these cases, research into the way cancer cells are likely to respond has raised the possibility that combining two targeted therapies will make them more effective.

Some experts believe such combinations of experimental-stage drugs could in future become commonplace as researchers hunt for better "targeted" treatments to disrupt the multiple signalling pathways that are used by cancer cells to proliferate and grow.

"In the spirit of personalising and stratifying cancer care, it is a logical step to combine new exciting molecules across pipelines and companies early on, to explore combined activity against cancer pathways," said Wolfgang Wein, head of oncology at German drugmaker Merck.

The latest collaboration involves Merck's experimental drug MSC1936369B and two experimental products from Sanofi, SAR245409 and SAR245408.

Each company will be responsible for conducting an initial Phase I study. Sanofi will be granted a licence to test MSC1936369B in combination with SAR245408, while Merck assesses its drug in combination with SAR245409. Financial terms of the deal were not disclosed.

Phase I is the first stage of clinical testing, so the new drug "cocktails" are still several years from reaching the market. (Editing by Jon Loades-Carter)