June 8 (Reuters) - Tango Therapeutics TNGX.O said on Monday an experimental drug combination showed strong early results in a small study of patients with advanced pancreatic cancer and that it plans to advance the treatment into late-stage testing.

Shares of the drug developer jumped 45% in premarket trading.

Here are some details:

• Tango said its drug vopimetostat, in combination with Revolution Medicines' RVMD.O daraxonrasib, shrank tumor in 11 of 12 patients with previously treated pancreatic ductal adenocarcinoma.

• The company said 90% of patients who received the combination survived without the disease worsening six months after treatment.

• The data comes a week after Revolution Medicines at the American Society of Clinical Oncology reported that daraxonrasib doubled survival and improved quality of life in patients with pancreatic cancer, a disease that remains hard to treat as it is often diagnosed late and responds poorly to existing therapies.

• The data is part of an ongoing early- to mid-stage stage trial testing vopimetostat with two of Revolution's drugs in patients with pancreatic or lung cancer whose tumors carry specific genetic changes.

• As of May 28, 59 patients with pancreatic cancer or non-small cell lung cancer had been treated in the study.

• The combination of vopimetostat and daraxonrasib was generally well tolerated, with most treatment-related side effects rated as mild or moderate, Tango said.

• A second combination involving vopimetostat and zoldonrasib shrunk tumors in 14 of 27 pancreatic cancer patients who were evaluated.

• For the late stage, Tango plans to test the vopimetostat-daraxonrasib combination in first-line pancreatic cancer patients with a genetic mutation known as MTAP deletion, pending discussions with regulators.

• Vopimetostat is an oral drug designed to target cancer cells with MTAP deletion. Tango said MTAP deletions occur in about 40% of pancreatic cancers and 15% of lung cancers.