Astex to Showcase Its Next-Generation Hypomethylating Agents Being Developed for Treatment of AML/MDS at the 2016 Annual Meeting of the American Society of Hematology

  • New clinical data to be presented in four oral presentations on guadecitabine (SGI-110)
    and ASTX727
  • Two new global Phase 3 studies commencing to investigate the potential of guadecitabine
    in the treatment of relapsed / refractory AML (ASTRAL-2) and relapsed / refractory MDS
    (ASTRAL-3)
  • Enrollment completed into the global Phase 3 clinical study of guadecitabine in adults with
    previously untreated AML who are not considered candidates for intensive induction
    chemotherapy (ASTRAL-1)

Pleasanton, CA, November 29, 2016. Astex Pharmaceuticals, a member of the Otsuka group, announced today that investigators collaborating with Astex will present results from several studies evaluating guadecitabine, its subcutaneous, next-generation hypomethylating agent; and ASTX727, its novel, oral hypomethylating agent at the 2016 Annual Meeting of the American Society of Hematology in San Diego, California, December 3 to 6.

The oral presentations are as follows:

  • Initial results of a Phase 2 Study of Guadecitabine (SGI-110), A Novel Subcutaneous (sc) Hypomethylating Agent, for Patients with Previously Untreated Intermediate-2 or High Risk Myelodysplastic Syndromes (MDS) or Chronic Myelomonocytic Leukemia (CMML) (Abstract #346). Dr. Guillermo Montalban-Bravo et al. Sunday, December 4, 10:15 am; Manchester
    Grand Hyatt, Grand Hall C.
  • Results of a Phase II study of Guadecitabine (SGI-110) in higher risk MDS, CMML or lowblast- count AML patients refractory to or relapsing after Azacitidine (AZA) treatment
    (Abstract #347). Dr. Marie Sebert et al. Sunday, December 4, 10:30 am; Manchester Grand Hyatt, Grand Hall C.
  • Long Term Survival and Clinical Complete Responses of Various Prognostic Subgroups in 103 Relapsed/Refractory Acute Myeloid Leukemia (r/r AML) Patients Treated with Guadecitabine
    (SGI-110) in Phase 2 Studies (Abstract #904). Dr. Naval Daver et al. Monday, December 5, 3:30 pm; Marriott Marquis San Diego Marina, San Diego Ballroom AB.
  • Successful Emulation of IV Decitabine Pharmacokinetics with an Oral Fixed-Dose Combination of the Oral Cytidine Deaminase Inhibitor (CDAi) E7727 with Oral Decitabine, in Subjects with Myelodysplastic Syndromes (MDS): Final Data of Phase 1 Study (Abstract #114). Dr. Guillermo Garcia-Manero et al. Saturday December 3, 10:45 am; Manchester Grand Hyatt, Grand Hall C.

In addition, a poster presentation entitled: Genetic determinants of response to guadecitabine (SGI- 110) in AML (Abstract #1680), Dr. Patricia L. Kropf et al., will be made on Saturday December 3, 9:30 am to 11 am in the San Diego Convention Center, Hall GH.

Data from the guadecitabine Phase 2 study (www.clinicaltrials.gov, NCT01261312) has helped to inform the design of the 800-patient, global Phase 3 study of guadecitabine in adults with previously
untreated AML who are not considered candidates for intensive induction chemotherapy (ASTRAL-1, www.clinicaltrials.gov, NCT02348489), and the newly announced global Phase 3 studies in relapsed / refractory AML (ASTRAL-2, www.clinicaltrials.gov, NCT02920008), and relapsed / refractory MDS or CMML (ASTRAL-3, www.clinicaltrials.gov, NCT02907359). Astex also announced today that enrollment into the ASTRAL-1 study is now complete. The data on ASTX727 being reported at ASH also informed the design of a Phase 2 randomized, cross-over study comparing ASTX727 to decitabine IV in higher risk MDS, which is ongoing.

“The data from these clinical studies helps to validate the development of these agents for the treatment of AML and MDS, potentially providing new treatment options for patients with these
aggressive hematological malignancies” said Mohammad Azab, President and Chief Medical Officer of Astex. “We are delighted to be working with some of the world’s leading experts in the treatment of hematological malignancies in bringing these next-generation therapies to patients.”

 About Guadecitabine (SGI-110)
Guadecitabine is a novel next-generation, small-molecule DNA hypomethylating agent formulated as a single, small-volume, subcutaneous injection. The product was designed to
deliver longer exposure to the active metabolite, decitabine, compared to IV decitabine, and more efficient delivery into key tissues, including the bone marrow. Guadecitabine
demonstrated activity in restoring silenced tumor suppressor gene expression in cancer cells by reversal of DNA methylation and inducing responses in previously treated MDS and AML
patients. Guadecitabine is currently being investigated in multiple clinical trials, including the ASTRAL series of studies and an extensive program of investigational studies in combination
with immunotherapy and other anti-neoplastic agents, for the treatment or a range of hematological malignancies and solid tumors.

About ASTX727
ASTX727 is a unique fixed-dose combination of the hypomethylating agent decitabine, the active ingredient in Dacogen®, and the novel cytidine deaminase inhibitor, E7727. ASTX727 was
designed to deliver decitabine by oral administration. By inhibiting cytidine deaminase, E7727 inhibits the major mechanism by which decitabine is degraded in the gut, and the combination
therefore permits the efficient oral delivery of decitabine at a low dose. Astex is completing a Phase 2 clinical study of ASTX727 in the treatment of intermediate and high risk myelodysplastic
syndromes (MDS). Guadecitabine and ASTX727 are investigational agents, and efficacy and safety have not been established. There is no certainty that these agents will become commercially available.

About Astex Pharmaceuticals
Astex is a leader in innovative drug discovery and development, committed to the fight against cancer and diseases of the central nervous system. Astex is developing a proprietary pipeline of
novel therapies and has a number of partnered products being developed under collaborations with leading pharmaceutical companies.

Astex is a member of the Otsuka Group, based in Japan. Otsuka is a global healthcare company with the corporate philosophy: “Otsuka–people creating new products for better health worldwide.”
Otsuka researches, develops, manufactures and markets innovative and original products, with a focus on pharmaceutical products for the treatment of diseases and nutraceutical products for the
maintenance of everyday health.

For more information about Astex Pharmaceuticals, please visit https://stagin.astx.co.uk
For more information about Otsuka Pharmaceutical, please visit http://www.otsuka.com/en/

CONTACT:
Martin Buckland
Chief Corporate Officer
Astex Pharmaceuticals, Inc.
4420 Rosewood Drive, Suite 200
Pleasanton, CA 94588
Tel: +1 (925) 560-0100
Email: email_mb