LONDON (Reuters) - After last month’s big clinical trial setback in lung cancer, AstraZeneca will seek to rebuild its oncology reputation next week when it unveils full details of two key clinical trials tackling the disease in different ways.

FILE PHOTO: The logo of AstraZeneca is seen on a medication package at a pharmacy in London April 28, 2014. REUTERS/Stefan Wermuth

The British drugmaker has already said the studies, known as PACIFIC and FLAURA, met their pre-defined goals but the exact scale of the benefit will only be disclosed at the European Society for Medical Oncology (ESMO) congress in Madrid on Sept. 9.

The PACIFIC study will reveal how much the infused immunotherapy drug Imfinzi can help with early or non-metastatic lung cancer, where it is not possible to operate.

There are currently no approved treatments for this stage of disease and strong data could open up a $1 billion-plus opportunity - though it will still be smaller than for late-stage disease, where a combination of Imfinzi and tremelimumab failed to work as hoped.

While details are being kept under wraps, doctors are optimistic. ESMO president-elect Solange Peters of the Centre Hospitalier Universitaire Vaudois in Lausanne told the Medscape website: “I’ve seen the data, and it’s absolutely exciting.”

AstraZeneca’s oncology business head Jamie Freedman, meanwhile, described the results as “potentially transformative”.

The FLAURA study will show how well AstraZeneca’s new pill Tagrisso holds lung cancer at bay in patients with a particular genetic mutation. In this case, doctors want evidence that it is substantially better than older medicines that act in a similar way.

The ESMO meeting, which runs from Sept. 8 to 12, will also be important for other drugmakers, with physicians and investors keen to see how Eli Lilly’s experimental CDK4/6 drug abemaciclib compares with marketed products from Pfizer and Novartis.

Bristol-Myers Squibb, Merck & Co and Roche will also give updates on how their immunotherapies are progressing across a range of clinical trials, while smaller companies will disclose data on other novel medicines.

These include U.S. biotech company Incyte, which on Thursday reported promising results for a small melanoma study testing its IDO drug epacadostat - a new kind of immunotherapy - with Merck’s established drug Keytruda.

The Incyte data were released in a scientific abstract posted online ahead of the ESMO congress.