Phase I study of 5-aza-2'-deoxycytidine in combination with valproic acid in non-small-cell lung cancer

Cancer Chemother Pharmacol. 2013 Jan;71(1):115-21. doi: 10.1007/s00280-012-1986-8. Epub 2012 Oct 9.


Purpose: Non-small-cell lung cancer (NSCLC) accounts for the majority of lung cancer and is the most common cause of cancer death in industrialized countries. Epigenetic modifications are observed universally during the tumorigenesis of lung cancer. The development of epigenetic-modulating agents utilizing the synergism between hypomethylating agents and histone deacetylase (HDAC) inhibitors provides a novel therapeutic approach in treating NSCLC.

Methods: We performed a phase I trial combining 5-aza-2'-deoxycytidine (decitabine) and valproic acid (VPA), in patients with advanced stage NSCLC. Patients were treated with escalating doses of decitabine (5-15 mg/m(2)) IV for 10 days in combination with VPA (10-20 mg/kg/day) PO on days 5-21 of a 28-day cycle. Pharmacokinetic and pharmacodynamic analysis included decitabine pharmacokinetics and fetal hemoglobin expression.

Results: Eight patients were accrued to this phase I study. All patients had advanced NSCLC and had received prior chemotherapy. Eastern Cooperative Oncology Group performance status was 0-2. Major toxicities included myelosuppression and neurotoxicity. Dose-limiting toxicity was seen in two patients suffering grade 3 neurotoxicity during cycle one including disorientation, lethargy, memory loss, and ataxia at dose level 1. One patient had grade 3 neutropenia at the de-escalated dose. No objective response was observed, and stable disease was seen in one patient. Fetal hemoglobin levels increased after cycle one in all seven patients with evaluable results.

Conclusions: We observed that decitabine and valproic acid are an effective combination in reactivating hypermethylated genes as demonstrated by re-expressing fetal hemoglobin. This combination in patients with advanced stage IV NSCLC, however, is limited by unacceptable neurological toxicity at a relatively low dosage. Combining hypomethylating agents with alternative HDAC inhibitors that lack the toxicity of VPA should be explored further.

Publication types

  • Clinical Trial, Phase I
  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Antineoplastic Combined Chemotherapy Protocols / administration & dosage
  • Antineoplastic Combined Chemotherapy Protocols / adverse effects
  • Antineoplastic Combined Chemotherapy Protocols / therapeutic use*
  • Azacitidine / administration & dosage
  • Azacitidine / analogs & derivatives
  • Carcinoma, Non-Small-Cell Lung / drug therapy*
  • Carcinoma, Non-Small-Cell Lung / pathology
  • Decitabine
  • Dose-Response Relationship, Drug
  • Drug Synergism
  • Female
  • Histone Deacetylase Inhibitors / administration & dosage
  • Histone Deacetylase Inhibitors / adverse effects
  • Histone Deacetylase Inhibitors / therapeutic use
  • Humans
  • Lung Neoplasms / drug therapy*
  • Lung Neoplasms / pathology
  • Male
  • Middle Aged
  • Neoplasm Staging
  • Treatment Outcome
  • Valproic Acid / administration & dosage


  • Histone Deacetylase Inhibitors
  • Valproic Acid
  • Decitabine
  • Azacitidine