Penciclovir pharmacokinetics after oral and rectal administration of famciclovir in African elephants (Loxodonta africana) shows that effective concentrations can be achieved from rectal administration, despite lower absorption.

OBJECTIVE: To evaluate the pharmacokinetics of famciclovir and its metabolite penciclovir following a single dose administered orally and rectally in African elephants (Loxodonta africana). ANIMALS: 15 African elephants (6 males and 9 females) of various ages. METHODS: Famciclovir (15 mg/kg) was administered orally or per rectum once, with at least a three-week washout period between administrations. Blood was collected at 13 different timepoints per administration for 6 elephants, occurring between February and March 2020. An additional 9 elephants were sampled at variable timepoints per administration utilizing a sparse sampling design between July 2020 and January 2021. Plasma famciclovir and penciclovir levels were measured via HPLC and fluorescence detection. Pharmacokinetic analysis was completed in the summer of 2021 using noncompartmental analysis and nonlinear mixed-effects modeling. RESULTS: Famciclovir was not detected in any sample, suggesting complete metabolism. Key pharmacokinetic parameters for penciclovir following oral administration were time to maximum concentration (tmax; 2.12 hours), area under the concentration-versus-time curve (AUC; 33.93 µg·h/mL), maximum observed concentration (Cmax; 3.73 µg/mL), and absorption half-life (t1/2; 0.65 hours). Following rectal administration, the values were: tmax, 0.65 hours; AUC, 15.62 µg·h/mL; Cmax, 2.52 µg/mL; and absorption t1/2, 0.13 hours. CONCLUSIONS: Famciclovir was rapidly metabolized to penciclovir. Oral administration resulted in slower absorption but higher maximum plasma concentration and higher AUC compared to rectal administration. CLINICAL RELEVANCE: African elephants administered famciclovir via oral and rectal routes resulted in measurable serum penciclovir, and these findings may be utilized by clinicians treating viral infections in this species.

Efficacy of valacyclovir and famciclovir in herpes zoster: A comparative study.

OBJECTIVES: The objective was to evaluate the efficacy of antiviral agent valacyclovir compared with famciclovir in the treatment of herpes zoster. MATERIALS AND METHODS: A comparative study was conducted over a period of 1 year. Data relevant to the study were collected from 60 patients, with active herpes zoster presenting to the outpatient department within 72 hr of the first occurrence of zoster rash. They were divided in to two groups of 30 patients each. The first group of patients received valacyclovir tablet 1000 mg thrice daily, whereas those in the second group were given famciclovir tablet 500 mg thrice daily. Both the drugs were given for 7 days. Periodic follow-up till 29th day was done for assessment of the effects of given drugs. RESULTS: Significant decrease was observed on comparison of pain scores between the two groups using the visual analog scale, with the drug valacyclovir, than in the famciclovir group at day 29. Furthermore, valacyclovir treatment accelerated the resolution of zoster associated pain in more number of patients compared with famciclovir. CONCLUSION: Oral valacyclovir administered during acute zoster infection for a period of 7 days offers significant benefit compared to famciclovir by providing a well tolerated and greater resolution of pain while maintaining the favorable safety profile, making valacyclovir more efficacious and a better drug in management of Herpes Zoster in comparison to famciclovir.

Effects of famciclovir in cats with spontaneous acute upper respiratory tract disease.

OBJECTIVES: The aim of this study was to assess the effects of famciclovir administration in cats with spontaneously acquired acute upper respiratory tract disease. METHODS: Twenty-four kittens with clinical signs of acute upper respiratory tract disease were randomly allocated to receive doxycycline (5 mg/kg PO q12h) alone (group D; n = 12) or with famciclovir (90 mg/kg PO q12h; group DF; n = 12) for up to 3 weeks. Clinical disease severity was scored at study entry and daily thereafter. Oculo-oropharyngeal swabs collected at study entry and exit were assessed using quantitative PCR for nucleic acids of feline herpesvirus type 1 (FHV-1), feline calicivirus (FCV), Chlamydia felis, Bordetella bronchiseptica and Mycoplasma felis. RESULTS: The median (range) age of cats was 1.5 (1-6) months in group D vs 1.6 (1-5) months in group DF (P = 0.54). Pathogens detected in oculo-oropharyngeal swabs at study entry included FCV (n = 13/24; 54%), M felis (n = 8/24; 33%), FHV-1 (n = 7/24; 29%), C felis (n = 7/24; 29%) and B bronchiseptica (n = 3/24; 12%). Median (range) duration of clinical signs was 11.5 (3-21) days in group DF and 11 (3-21) days in group D (P = 0.75). Median (range) total disease score at the end of the study did not differ between groups (group D 1 [1-1] vs group DF 1 [1-3]; P = 0.08). CONCLUSIONS AND RELEVANCE: This study revealed no significant difference in response to therapy between cats treated with doxycycline alone or with famciclovir; cats improved rapidly in both groups. However, identification of FHV-1 DNA was relatively uncommon in this study and clinical trials focused on FHV-1-infected cats are warranted to better evaluate famciclovir efficacy.

HSV-associated erythema multiforme in a patient after hematopoietic stem cell transplantation.

Herpes simplex virus (HSV)-associated erythema multiforme (HAEM) is an acute and self-limiting mucocutaneous hypersensitivity reaction triggered by herpes virus infections. We reported a patient with HAEM after hematopoietic stem cell transplantation (HSCT). A 55-year-old man received HSCT 7 months ago. He suffered from chronic graft versus host disease 4 months after HSCT and was treated with prednisone and tacrolimus. One week ago, he developed generalized macules with leukopenia. Dermatological examination revealed multiple iris-like erythemas on his trunk and extremities. The skin lesions and leukopenia resolved upon anti-HSV treatment.

Comparison Of Efficacy Of Two Different Doses Of Famciclovir In The Prevention And Treatment Of Postherpetic Neuralgia.

BACKGROUND: Herpes Zoster is a common dermatological ailment. Various treatment modalities are in use for prevention of Post Herpetic Neuralgia (PHN) which is the most common complication of herpes zoster. Our study aimed to compare the efficacy of famciclovir 250 mg versus 500 mg in this regard. METHODS: The study was conducted at a tertiary care hospital recruiting subjects by using simple random sampling, group A patients received famciclovir 250 mg thrice daily for 1 week while group B patients were administered 500 mg. Follow ups were arranged at 2, 4 & 12 weeks. Efficacy was assessed by pain evaluation as per numeric rating scale and counting number of skin lesions. PHN was taken as persistent pain at 4 weeks follow up. All the statistical analysis was done using SPSS. RESULTS: A total of 30 patients were included in the study with each group (A & B) containing 15 patients each. Both dosing groups were statistically consistent with each other in reducing pain at 2, 4 and 12 weeks follow up. Skin lesions were not observed after 2 weeks in either group. The median of difference of pain scores at 2 weeks was similar as at 4 weeks. CONCLUSION: Famciclovir 250 mg thrice daily for one week is equally effective as 500 mg in treating active herpes zoster and prevention of PHN. However, long term follow-up is required for assessing the true incidence of PHN.

Prophylactic and therapeutic effects of twice-daily famciclovir administration on infectious upper respiratory disease in shelter-housed cats.

OBJECTIVES: In humans with herpetic disease, early or pre-emptive famciclovir therapy reduces disease duration and severity. This prospective, masked, placebo-controlled study tested therapeutic and prophylactic effects of two famciclovir doses given to cats for 7 days following shelter entry. METHODS: Cats were assigned to prophylactic or therapeutic study arms based on clinical evidence of herpetic disease at study entry. Cats in the therapeutic arm received no treatment (n = 19), placebo (lactose; n = 18) or famciclovir at ~30 (n = 21) or ~90 mg/kg (n = 20) PO q12h for 7 days. Cats in the prophylactic arm received no treatment (n = 25) or famciclovir at ~30 (n = 28) or ~90 mg/kg (n = 27) PO q12h for 7 days. Disease scores, body weight, conjunctival feline herpesvirus 1 (FHV-1) shedding, and adoption rates were recorded on days 1 (admission), 8 (end of therapy) and 15 (1 week after cessation of therapy). RESULTS: No significant differences in clinical scores were observed among groups in the prophylactic or therapeutic arms at any of the three time points. However, within the therapeutic arm, viral shedding on day 8 was significantly higher in cats receiving no treatment than in those receiving ~30 or ~90 mg/kg famciclovir, and this effect persisted 1 week after famciclovir was stopped (day 15) only in cats receiving ~30 mg/kg, although this approached significance in cats receiving ~90 mg/kg. No significant differences in adoption rates were detected among groups in either arm throughout the study. CONCLUSIONS AND RELEVANCE: Although we did not demonstrate a statistically or clinically significant effect of famciclovir administration upon clinical signs of infectious upper respiratory disease or adoption, when it was administered at ~30 or ~90 mg/kg q12h for 1 week famciclovir reduced conjunctival FHV-1 shedding. This suggests a potential role in interrupting the infectious cycle within a shelter population; however, cost in time and resources, and stress and pathogen transmission induced by oral administration should be considered.

Comparison of Famciclovir, Valaciclovir, and Brivudine Treatments in Adult Immunocompetent Patients With Herpes Zoster.

Herpes zoster (HZ) is a common disease characterized by the recurrence of varicella zoster, that stays dormant in sensory ganglia. The primary goal of this study was to compare efficiencies of famciclovir, valaciclovir, and brivudine in terms of pain relief in HZ patients. Records of patients who were admitted to the Dermatology Clinic of our hospital due to acute HZ between the years 2012 and 2014 were retrospectively analyzed. Treatment decisions were at the discretion of caring physicians as valaciclovir (VACV), famciclovir (FCV), and brivudine (BRV) based on the clinical observations. BRV, FCV, and VACV were effective in treating pain in acute HZ. There was no significant difference between mild and moderate HZ patients. In severe cases, a significant reduction in intensity of pain was observed on day 3 in the BRV group, on day 7 in the FCV group, and at 2-3 weeks in the VACV group. There were no significant side effects observed in any of the groups. Results of this study indicate that brivudine may be the first choice in severe HZ cases as it controls pain earlier and is easier to use because of its once daily administration.

WHO guidelines for the treatment of genital herpes simplex virus

Rationale for the guidelines: Since the publication of the World Health Organization (WHO) Guidelines for the management of sexually transmitted infections in 2003, changes in the epidemiology of STIs and advancements in prevention, diagnosis and treatment necessitate changes in STI management. These guidelines provide updated treatment recommendations for genital HSV infection based on the most recent evidence; they form one of several modules of guidelines for specific STIs. Other modules will focus on treatments for Neisseria gonorrhoeae (gonorrhoea), C. trachomatis (chlamydial infection) and Treponema pallidum (syphilis). In addition, future work will provide guidance for syphilis screening and treatment of pregnant women, STI syndromic approach, clinical management, STI prevention, and treatments of other STIs. It is strongly recommended that countries take updated global guidance into account as they establish standardized national protocols, adapting this guidance to the local epidemiological situation and antimicrobial susceptibility data. The objectives of these guidelines are: to provide evidence-based guidance on treatment of genital HSV infection; and to support countries to update their national guidelines for treatment of genital HSV infection.