title: Response of HIV RNA to didanosine as a predictive marker of survival.
abstract: OBJECTIVE
  To evaluate whether early changes in viraemia in response to didanosine (ddI) predict death and occurrence of new AIDS-defining events.
  
  
  METHODS
  Forty-three patients were followed during ddI treatment with sequential determinations of serum viraemia, mutations associated with drug resistance, CD4 counts and clinical evaluation. Patients were stratified into two groups of equal size, responders and nonresponders, using the median of individual changes in viraemia 1 month after initiation of ddI therapy.
  
  
  RESULTS
  After 1 month of ddI, mean viraemia decreased by 0.35 log RNA copies/ml of serum (P < 0.001) in the population. A significant difference in survival (median, 14 and 35 months in nonresponders and responders, respectively; log rank, P = 0.004) and in the delay to the occurrence of new AIDS-defining events (median, 8 and 33 months in nonresponders and responders, respectively; log rank, P = 0.018) was observed. After stratification for presence of AIDS before starting ddI, viraemia response at 1 month remained predictive of both overall and AIDS-defining event-free survival (log rank, P = 0.0006 and P = 0.01). After a similar stratification for initial CD4, viraemia response still predicted overall survival (log rank, P = 0.009), but its predictive value for AIDS-defining event-free survival did not reach statistical significance (P = 0.12). High initial levels of HIV RNA, presence of mutation 215 or previous duration of zidovudine therapy were not predictive of survival.
  
  
  CONCLUSIONS
  In patients treated with ddI, changes in viraemia at 1 month predict survival independently of initial AIDS diagnosis and initial CD4 counts.
authors.affiliation: Central Laboratory of Virology, Geneva University Hospital, Switzerland.
authors.forename: S
authors.initials: S
authors.lastname: Yerly
authors.forename: L
authors.initials: L
authors.lastname: Kaiser
authors.forename: B
authors.initials: B
authors.lastname: Mermillod
authors.forename: C
authors.initials: C
authors.lastname: Baumberger
authors.forename: B
authors.initials: B
authors.lastname: Hirschel
authors.forename: L
authors.initials: L
authors.lastname: Perrin
mesh_terms: D000163:Acquired Immunodeficiency Syndrome / Q000188:drug therapy* / Q000401:mortality / Q000821:virology; D016049:Didanosine / Q000627:therapeutic use*; D005500:Follow-Up Studies; D006678:HIV / Q000187:drug effects* / Q000235:genetics; D006801:Humans; D011379:Prognosis; D012367:RNA, Viral / Q000032:analysis*; D017741:Survivors; D014766:Viremia / Q000188:drug therapy
chemical_list: D012367:RNA, Viral; D016049:Didanosine