NuCana Announces Positive Results of NUC-1031 (Acelarin®) in Advanced Ovarian Cancer at ESMO 2017

Acelarin combination with carboplatin achieved 96% disease control rate and 39% response rate in patients with recurrent ovarian cancer

Edinburgh, United Kingdom, September 12, 2017 (GLOBE NEWSWIRE) – NuCana plc, a clinical-stage biopharmaceutical company developing a portfolio of novel anti-cancer medicines called ProTides®, announced the presentation of data from its recently completed trial of its lead product candidate, NUC-1031 (Acelarin®), at the European Society for Medical Oncology (ESMO) 2017 Congress held September 8^th-12^th, 2017 in Madrid, Spain. Results from NuCana’s Phase 1b trial showed that Acelarin, when combined with carboplatin, was well tolerated and demonstrated clinical activity in women with recurrent platinum-resistant and platinum-sensitive ovarian cancer.  An overall response rate of 39% was observed amongst the 23 evaluable patients, including 1 (4%) who achieved a complete response, 8 (35%) with partial responses, and 13 (57%) with stable disease that lasted at least 12 weeks.  This yielded an overall disease control rate of 96% (22 patients). The responses were durable, with an average progression free survival of 7.4 months. The most common adverse events across all dose levels were neutropaenia, leukopaenia and thrombocytopaenia. No unexpected adverse events were observed with the combination to date.

All patients in the study were previously treated with an average of three prior chemotherapy regimens.  Seventeen of the evaluable patients were either refractory or resistant to their last platinum-containing regimen.

“The fact that the Acelarin combination with carboplatin achieved these results in heavily pre-treated and platinum-resistant patients clearly demonstrates Acelarin is a very active agent,” said Dr. Sarah Blagden, Associate Professor of Experimental Cancer Medicine at the University of Oxford and Chief Investigator of the Phase 1b study.  Professor Blagden added, “importantly,  the favorable toxicity profile of Acelarin enabled us to combine it with carboplatin at AUC 5, whereas with gemcitabine, carboplatin has to be given at AUC 4.  Thus, we are able to deliver both Acelarin and carboplatin at their optimal dose.”

Hugh Griffith, NuCana’s Chief Executive Officer, said: “The high disease control rate and durable responses achieved with the combination of Acelarin and carboplatin are exciting.  We remain focused on advancing Acelarin’s development for the treatment of patients with ovarian cancer as well as exploring its use for the treatment of other solid tumours."

About NuCana

NuCana® is a clinical-stage biopharmaceutical company focused on significantly improving treatment outcomes for cancer patients by applying our ProTide^™ technology to transform some of the most widely prescribed chemotherapy agents, nucleoside analogs, into more effective and safer medicines. While these conventional agents remain part of the standard of care for the treatment of many solid tumours, their efficacy is limited by cancer cell resistance mechanisms and they are often poorly tolerated. Utilising our proprietary technology, we are developing new medicines, ProTides, designed to overcome key cancer resistance mechanisms and generate much higher concentrations of anti-cancer metabolites in cancer cells. Our most advanced ProTide candidates, Acelarin^® and NUC-3373, are new chemical entities derived from the nucleoside analogs gemcitabine and 5-fluorouracil, respectively, two widely used chemotherapy agents. Acelarin is currently being evaluated in four clinical studies across several solid tumour indications, including ovarian cancer, biliary cancer and pancreatic cancer. NUC-3373 is currently in a Phase 1 study for the potential treatment of a wide range of advanced solid tumour cancers.  For more information, please visit: www.nucana.com.

Forward-Looking Statements

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For more information, please contact:

Hugh Griffith

Chief Executive Officer

+44 131 248 3660

info@nucana.com

Westwicke Partners

Chris Brinzey

+1 339-970-2843

Chris.brinzey@westwicke.com