The pharmacokinetics and safety of the L-valyl ester pro-drug of acyclovir, valaciclovir (256U87), were investigated in two phase I, placebo-controlled trials in normal volunteers. These included a single-dose study with doses from 100 to 1000 mg (single cohort) and a multiple-dose investigation with doses from 250 to 2000 mg (five separate cohorts). In each cohort, eight subjects received valaciclovir and four subjects received placebo. Pharmacokinetic findings for valaciclovir and acyclovir were consistent in the two studies. Valaciclovir was rapidly and extensively converted to acyclovir, resulting in significantly greater acyclovir bioavailability (approximately threefold to fivefold) compared with that historically observed with high-dose (800 mg) oral acyclovir. At the higher valaciclovir doses, acyclovir maximum concentration and daily area under the concentration-time curve approximated those obtained with intravenous acyclovir. The favorable safety profile and enhanced acyclovir bioavailability from valaciclovir administration has prompted additional clinical evaluations for zoster and herpes simplex virus treatment, as well as cytomegalovirus suppression in immunocompromised patients.
Human cytomegalovirus (CMV) has been associated with vascular pathology. In vivo, CMV is present in vessel wall cells during acute and chronic infections as well as in atherosclerotic lesions. CMV nucleic acids and proteins have also been detected within Kaposi's sarcoma lesions. Because of these associations, we studied the interaction of CMV with human endothelial cells with particular attention to its oncogenicity in this cell type. Our data demonstrate that human endothelial cells are permissive to viral replication but that the viral replication cycle is delayed compared with fibroblast cells. Persistent infections can result with minimal cytopathology. CMV can transform these cells to anchorage-independent growth, and noninfectious virus is still capable of inducing this transforming event. Our results demonstrate that productive or persistent CMV infection of endothelial cells and viral-induced transformation can occur, thus providing an in vitro correlate of in vivo events.
One-hundred and two patients with hemophilia A, hemophilia B, or acquired antibody to factor VIII who had undergone invasive procedures were cross referenced with patients participating in an ongoing prospective natural history study of HIV-1 infection in hemophiliacs. Matching revealed that HIV-1 status was known for 83 patients (83%) who had undergone 169 procedures between July 1979 and April 1988. Invasive procedures were classified as clean in 108 patients (63.9%), clean-contaminated in 45 (26.6%), contaminated in 2 (1.2%), and infected in 14 (8.3%). Wound infection rates by HIV-1 status were as follows (95% confidence intervals): HIV+ 1.4% (0% to 5%), HIV- 0% (0% to 9%), and procedure before testing HIV+ 1.5% (0% to 6%). There were no significant differences between the wound infection rates of HIV-positive and HIV-negative hemophiliacs nor in the wound infection rate among all three subgroups of patients (p greater than 0.5, Fisher's Exact Test). We conclude that surgery in HIV-1-infected patients who have not progressed to AIDS does not entail an increased risk of postoperative wound infections.
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