Michael Ritter
Merck & Co.
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The New England Journal of Medicine | 2015
Elmar A. Joura; Anna R. Giuliano; Ole-Erik Iversen; Céline Bouchard; Constance Mao; Jesper Mehlsen; Edson D. Moreira; Yuen Ngan; Lone Kjeld Petersen; Eduardo Lazcano-Ponce; Punnee Pitisuttithum; Jaime Alberto Restrepo; Gavin Stuart; Linn Woelber; Yuh Cheng Yang; Jack Cuzick; Suzanne M. Garland; Warner K. Huh; Susanne K. Kjaer; Oliver M. Bautista; Ivan S. F. Chan; Joshua Chen; Richard Gesser; Erin Moeller; Michael Ritter; Scott Vuocolo; Alain Luxembourg
BACKGROUND The investigational 9-valent viruslike particle vaccine against human papillomavirus (HPV) includes the HPV types in the quadrivalent HPV (qHPV) vaccine (6, 11, 16, and 18) and five additional oncogenic types (31, 33, 45, 52, and 58). Here we present the results of a study of the efficacy and immunogenicity of the 9vHPV vaccine in women 16 to 26 years of age. METHODS We performed a randomized, international, double-blind, phase 2b-3 study of the 9vHPV vaccine in 14,215 women. Participants received the 9vHPV vaccine or the qHPV vaccine in a series of three intramuscular injections on day 1 and at months 2 and 6. Serum was collected for analysis of antibody responses. Swabs of labial, vulvar, perineal, perianal, endocervical, and ectocervical tissue were obtained and used for HPV DNA testing, and liquid-based cytologic testing (Papanicolaou testing) was performed regularly. Tissue obtained by means of biopsy or as part of definitive therapy (including a loop electrosurgical excision procedure and conization) was tested for HPV. RESULTS The rate of high-grade cervical, vulvar, or vaginal disease irrespective of HPV type (i.e., disease caused by HPV types included in the 9vHPV vaccine and those not included) in the modified intention-to-treat population (which included participants with and those without prevalent infection or disease) was 14.0 per 1000 person-years in both vaccine groups. The rate of high-grade cervical, vulvar, or vaginal disease related to HPV-31, 33, 45, 52, and 58 in a prespecified per-protocol efficacy population (susceptible population) was 0.1 per 1000 person-years in the 9vHPV group and 1.6 per 1000 person-years in the qHPV group (efficacy of the 9vHPV vaccine, 96.7%; 95% confidence interval, 80.9 to 99.8). Antibody responses to HPV-6, 11, 16, and 18 were noninferior to those generated by the qHPV vaccine. Adverse events related to injection site were more common in the 9vHPV group than in the qHPV group. CONCLUSIONS The 9vHPV vaccine prevented infection and disease related to HPV-31, 33, 45, 52, and 58 in a susceptible population and generated an antibody response to HPV-6, 11, 16, and 18 that was noninferior to that generated by the qHPV vaccine. The 9vHPV vaccine did not prevent infection and disease related to HPV types beyond the nine types covered by the vaccine. (Funded by Merck; ClinicalTrials.gov number, NCT00543543).
Journal of Hypertension | 1995
D. A. Sica; Man‐Wai Lo; Wayne Shaw; William F. Keane; T. W. B. Gehr; C. E. Halstenson; K. Lipschutz; C. I. Furtek; Michael Ritter; Shahnaz Shahinfar
Aim: To determine the effect of renal insufficiency on the pharmacokinetics and pharmacodynamics of losartan (MK-954) and its metabolite E3174 Patients and methods: A two-center, unblinded trial was performed in 18 patients (age range 31–63 years) with various degrees of renal function grouped according to the renal clearance of creatinine: group I, creatinine clearance >75 ml/min; group II, creatinine clearance 30–74 ml/min; group III, creatinine clearance 10–29 ml/min (n=6 in all groups). Losartan (100mg/day) was administered under supervised conditions for seven consecutive days. Plasma samples were taken for up to 60 h and 24-h urine collections were made following the final dose of losartan (on day 7) to determine losartan and E 3174 concentrations, with simultaneous measurements of blood pressure and the pulse rate Results: The pharmacokinetic parameters for losartan and E3174 changed inconsequentially across the range of renal insufficiency. For losartan, renal clearance decreased from 50± 19 ml/min in group I to 2.3 ±0.9 ml/min in group III (P<0.05). For E31 74, although the renal clearance decreased from 16±4.1 ml/min in group I to 1.3 ±0.8 ml/min in group III (P<0.05), the area under the plasma concentration curve did not change Conclusions: The steady-state areas under the curve of losartan and E3174 are not significantly changed with renal impairment. The renal clearance of losartan decreases with renal impairment but since only a small percentage of the dose is ordinarily eliminated by the kidney, the demonstrated reduction in clearance is clinically irrelevant. The renal clearance of E3174 also decreases with renal impairment, but the steady-state area under the curve does not increase with increasing degrees of renal insufficiency. These pharmacokinetic alterations do not warrant dose adjustment in the face of renal insufficiency
JAMA | 2016
Ole-Erik Iversen; Maria Jose Miranda; Angels Ulied; Terje Soerdal; Erica Lazarus; Kulkanya Chokephaibulkit; Stan L. Block; Ales Skrivanek; Abdul Ghani Nur Azurah; Siew Moy Fong; Vladimír Dvorak; Kyung Hyo Kim; Ramon M. Cestero; Matitiahu Berkovitch; Mehmet Ceyhan; Misoo C. Ellison; Michael Ritter; Shuai S. Yuan; Mark J. DiNubile; Alfred J. Saah; Alain Luxembourg
Importance Human papillomavirus (HPV) infections cause anogenital cancers and warts. The 9-valent HPV vaccine provides protection against 7 high-risk types of HPV responsible for 90% of cervical cancers and 2 other HPV types accounting for 90% of genital warts. Objective To determine whether HPV type-specific antibody responses would be noninferior among girls and boys aged 9 to 14 years after receiving 2 doses of the 9-valent HPV vaccine compared with adolescent girls and young women aged 16 to 26 years receiving 3 doses. Design, Setting, and Participants Open-label, noninferiority, immunogenicity trial conducted at 52 ambulatory care sites in 15 countries. The study was initiated on December 16, 2013, with the last participant visit for this report on June 19, 2015. Five cohorts were enrolled: (1) girls aged 9 to 14 years to receive 2 doses 6 months apart (n = 301); (2) boys aged 9 to 14 years to receive 2 doses 6 months apart (n = 301); (3) girls and boys aged 9 to 14 years to receive 2 doses 12 months apart (n = 301); (4) girls aged 9 to 14 years to receive 3 doses over 6 months (n = 301); and (5) a control group of adolescent girls and young women aged 16 to 26 years to receive 3 doses over 6 months (n = 314). Interventions Two doses of the 9-valent HPV vaccine administered 6 or 12 months apart or 3 doses administered over 6 months. Main Outcomes and Measures The primary end point was prespecified as the antibody response against each HPV type assessed 1 month after the last dose using a competitive immunoassay. Each of the three 2-dose regimens was compared with the standard 3-dose schedule in adolescent girls and young women using a noninferiority margin of 0.67 for the ratio of the antibody geometric mean titers. Results Of the 1518 participants (753 girls [mean age, 11.4 years]; 451 boys [mean age, 11.5 years]; and 314 adolescent girls and young women [mean age, 21.0 years]), 1474 completed the study and data from 1377 were analyzed. At 4 weeks after the last dose, HPV antibody responses in girls and boys given 2 doses were noninferior to HPV antibody responses in adolescent girls and young women given 3 doses (P < .001 for each HPV type). Compared with adolescent girls and young women who received 3 doses over 6 months, the 1-sided 97.5% CIs for the ratio of HPV antibody geometric mean titers at 1 month after the last dose across the 9 HPV subtypes ranged from 1.36 to ∞ to 2.50 to ∞ for girls who received 2 doses 6 months apart; from 1.37 to ∞ to 2.55 to ∞ for boys who received 2 doses 6 months apart; and from 1.61 to ∞ to 5.36 to ∞ for girls and boys who received 2 doses 12 months apart. Conclusions and Relevance Among girls and boys aged 9 to 14 years receiving 2-dose regimens of a 9-valent HPV vaccine separated by 6 or 12 months, immunogenicity 4 weeks after the last dose was noninferior to a 3-dose regimen in a cohort of adolescent girls and young women. Further research is needed to assess persistence of antibody responses and effects on clinical outcomes. Trial Registration clinicaltrials.gov Identifier: NCT01984697.
Pediatrics | 2016
Edson D. Moreira; Stan L. Block; Daron G. Ferris; Anna R. Giuliano; Ole Erik Iversen; Elmar A. Joura; Pope Kosalaraksa; Andrea Schilling; Pierre Van Damme; Jacob Bornstein; F. Xavier Bosch; Sophie Pils; Jack Cuzick; Suzanne M. Garland; Warner K. Huh; Susanne K. Kjaer; Hong Qi; Donna Hyatt; Jason Martin; Erin Moeller; Michael Ritter; Martine Baudin; Alain Luxembourg
OBJECTIVES: The overall safety profile of the 9-valent human papillomavirus (9vHPV) vaccine was evaluated across 7 Phase III studies, conducted in males and females (nonpregnant at entry), 9 to 26 years of age. METHODS: Vaccination was administered as a 3-dose regimen at day 1, and months 2 and 6. More than 15 000 subjects received ≥1 dose of 9vHPV vaccine. In 2 of the studies, >7000 control subjects received ≥1 dose of quadrivalent HPV (qHPV) vaccine. Serious and nonserious adverse events (AEs) and new medical conditions were recorded throughout the study. Subjects testing positive for pregnancy at day 1 were not vaccinated; those who became pregnant after day 1 were discontinued from further vaccination until resolution of the pregnancy. Pregnancies detected after study start (n = 2950) were followed to outcome. RESULTS: The most common AEs (≥5%) experienced by 9vHPV vaccine recipients were injection-site AEs (pain, swelling, erythema) and vaccine-related systemic AEs (headache, pyrexia). Injection-site AEs were more common in 9vHPV vaccine than qHPV vaccine recipients; most were mild-to-moderate in intensity. Discontinuations and vaccine-related serious AEs were rare (0.1% and <0.1%, respectively). Seven deaths were reported; none were considered vaccine related. The proportions of pregnancies with adverse outcome were within ranges reported in the general population. CONCLUSIONS: The 9vHPV vaccine was generally well tolerated in subjects aged 9 to 26 years with an AE profile similar to that of the qHPV vaccine; injection-site AEs were more common with 9vHPV vaccine. Its additional coverage and safety profile support widespread 9vHPV vaccination.
The Lancet | 2017
Warner K. Huh; Elmar A. Joura; Anna R. Giuliano; Ole Erik Iversen; Rosires Pereira de Andrade; Kevin A. Ault; Deborah Bartholomew; Ramon M. Cestero; Edison Natal Fedrizzi; Angelica Lindén Hirschberg; Marie-Hélène Mayrand; Ángela María Ruiz-Sternberg; Jack T. Stapleton; Dorothy J. Wiley; Alex Ferenczy; Robert J. Kurman; Brigitte M. Ronnett; Mark H. Stoler; Jack Cuzick; Suzanne M. Garland; Susanne K. Kjaer; Oliver M. Bautista; Richard M. Haupt; Erin Moeller; Michael Ritter; Christine Roberts; Christine Shields; Alain Luxembourg
BACKGROUND Primary analyses of a study in young women aged 16-26 years showed efficacy of the nine-valent human papillomavirus (9vHPV; HPV 6, 11, 16, 18, 31, 33, 45, 52, and 58) vaccine against infections and disease related to HPV 31, 33, 45, 52, and 58, and non-inferior HPV 6, 11, 16, and 18 antibody responses when compared with quadrivalent HPV (qHPV; HPV 6, 11, 16, and 18) vaccine. We aimed to report efficacy of the 9vHPV vaccine for up to 6 years following first administration and antibody responses over 5 years. METHODS We undertook this randomised, double-blind, efficacy, immunogenicity, and safety study of the 9vHPV vaccine study at 105 study sites in 18 countries. Women aged 16-26 years old who were healthy, with no history of abnormal cervical cytology, no previous abnormal cervical biopsy results, and no more than four lifetime sexual partners were randomly assigned (1:1) by central randomisation and block sizes of 2 and 2 to receive three intramuscular injections over 6 months of 9vHPV or qHPV (control) vaccine. All participants, study investigators, and study site personnel, laboratory staff, members of the sponsors study team, and members of the adjudication pathology panel were masked to vaccination groups. The primary outcomes were incidence of high-grade cervical disease (cervical intraepithelial neoplasia grade 2 or 3, adenocarcinoma in situ, invasive cervical carcinoma), vulvar disease (vulvar intraepithelial neoplasia grade 2/3, vulvar cancer), and vaginal disease (vaginal intraepithelial neoplasia grade 2/3, vaginal cancer) related to HPV 31, 33, 45, 52, and 58 and non-inferiority (excluding a decrease of 1·5 times) of anti-HPV 6, 11, 16, and 18 geometric mean titres (GMT). Tissue samples were adjudicated for histopathology diagnosis and tested for HPV DNA. Serum antibody responses were assessed by competitive Luminex immunoassay. The primary evaluation of efficacy was a superiority analysis in the per-protocol efficacy population, supportive efficacy was analysed in the modified intention-to-treat population, and the primary evaluation of immunogenicity was a non-inferiority analysis. The trial is registered with ClinicalTrials.gov, number NCT00543543. FINDINGS Between Sept 26, 2007, and Dec 18, 2009, we recruited and randomly assigned 14 215 participants to receive 9vHPV (n=7106) or qHPV (n=7109) vaccine. In the per-protocol population, the incidence of high-grade cervical, vulvar and vaginal disease related to HPV 31, 33, 45, 52, and 58 was 0·5 cases per 10 000 person-years in the 9vHPV and 19·0 cases per 10 000 person-years in the qHPV groups, representing 97·4% efficacy (95% CI 85·0-99·9). HPV 6, 11, 16, and 18 GMTs were non-inferior in the 9vHPV versus qHPV group from month 1 to 3 years after vaccination. No clinically meaningful differences in serious adverse events were noted between the study groups. 11 participants died during the study follow-up period (six in the 9vHPV vaccine group and five in the qHPV vaccine group); none of the deaths were considered vaccine-related. INTERPRETATION The 9vHPV vaccine prevents infection, cytological abnormalities, high-grade lesions, and cervical procedures related to HPV 31, 33, 45, 52, and 58. Both the 9vHPV vaccine and qHPV vaccine had a similar immunogenicity profile with respect to HPV 6, 11, 16, and 18. Vaccine efficacy was sustained for up to 6 years. The 9vHPV vaccine could potentially provide broader coverage and prevent 90% of cervical cancer cases worldwide. FUNDING Merck & Co, Inc.
Human Vaccines & Immunotherapeutics | 2015
Alain Luxembourg; Darron R. Brown; Céline Bouchard; Anna R. Giuliano; Ole Erik Iversen; Elmar A. Joura; Mary E. Penny; Jaime Alberto Restrepo; Josefina Romaguera; Roger Maansson; Erin Moeller; Michael Ritter; Joshua Chen
Our objective was to develop a multivalent prophylactic HPV vaccine that protects against infection and disease caused by HPV16/18 (oncogenic types in existing prophylactic vaccines) plus additional oncogenic types by conducting 3 Phase II studies comparing the immunogenicity (i.e., anti-HPV6/11/16/18 geometric mean titers [GMT]) and safety of 7 vaccine candidates with the licensed quadrivalent HPV6/11/16/18 vaccine (qHPV vaccine) in young women ages 16–26. In the first study (Study 1), subjects received one of 3 dose formulations of an 8-valent HPV6/11/16/18/31/45/52/58 vaccine or qHPV vaccine (control). In Study 2, subjects received one of 3 dose formulations (termed low-, mid-, and high-dose formulations, respectively) of a 9-valent HPV6/11/16/18/31/33/45/52/58 vaccine (9vHPV vaccine) or qHPV vaccine (control). In Study 3, subjects concomitantly received qHPV vaccine plus 5-valent HPV31/33/45/52/58 or qHPV vaccine plus placebo (control). All vaccines were administered at day 1/month 2/month 6. In studies 1 and 3, anti-HPV6/11/16/18 GMTs at month 7 were non-inferior in the experimental arms compared with the control arm; however, there was a trend for lower antibody responses for all 4 HPV types. In Study 2, this immune interference was overcome with the mid- and high-dose formulations of the 9vHPV vaccine by increasing antigen and adjuvant doses. In all 3 studies, all vaccine candidates were strongly immunogenic with respect to HPV31/33/45/52/58 and were well tolerated. Based on the totality of the results, the middle dose formulation of the 9vHPV vaccine was selected for Phase III evaluation. Each 0.5mL dose contains 30μg/40μg/60μg/40μg/20μg/20μg/20μg/20μg/20μg of HPV6/11/16/18/31/33/45/52/58 virus-like particles, and 500μg of amorphous aluminum hydroxyphosphate sulfate adjuvant.ClinicalTrials.gov numbers NCT00260039, NCT00543543, and NCT00551187.
Contemporary Clinical Trials | 2015
Alain Luxembourg; Oliver M. Bautista; Erin Moeller; Michael Ritter; Joshua Chen
BACKGROUND The 9-valent human papillomavirus (HPV) (9vHPV) vaccine targets the four HPV types (6/11/16/18) covered by the licensed quadrivalent HPV (qHPV) vaccine and five additional types (31/33/45/52/58). A large outcome trial of 9vHPV vaccine was conducted. METHODS An active control (qHPV vaccine) was used because a placebo is not ethically acceptable. Since qHPV vaccine is (and 9vHPV vaccine was anticipated to be) highly efficacious against HPV 6/11/16/18, low incidence of HPV 6/11/16/18-associated disease was expected. Consequently, an efficacy comparison of 9vHPV versus qHPV vaccine for HPV 6/11/16/18 would have been prohibitively large in size. Moreover, no minimum antibody level predicting protection against infection or disease is defined for HPV vaccination. As an alternative approach, the two vaccines were compared using immunogenicity bridging for HPV 6/11/16/18 and clinical efficacy for HPV 31/33/45/52/58. RESULTS The two co-primary objectives were to demonstrate: (1) non-inferior anti-HPV 6/11/16/18 antibody response; and (2) superior efficacy in HPV 31/33/45/52/58-related clinical outcome, for 9vHPV vaccine versus qHPV vaccine. For HPV 6/11/16/18, supportive analyses included a non-inferiority assessment of the percent risk reduction (compared to historical placebo) for 9vHPV versus qHPV vaccine. CONCLUSIONS A Phase III study of 9vHPV vaccine was successfully implemented. Experience from this study design may be applicable when developing a multivalent vaccine covering the same serotypes as an existing vaccine plus additional serotypes and there is no immune correlate of protection. Also, this study established that efficacy of a new HPV vaccine may be demonstrated using immunogenicity endpoints, which may open new options in HPV vaccine development.
The Journal of Clinical Pharmacology | 2003
Tania Z. Dickson; Joann Zagrobelny; Charles Lin; Michael Ritter; Duane Snavely; Denise Ramjit; Shahnaz Shahinfar; Man‐Wai Lo
The pharmacokinetics and pharmacodynamics of 7 days of treatment with losartan 50 mg/hydrochlorothiazide 12.5 mg were evaluated in 14 patients with normal renal function and in 12 patients with mild to moderate renal impairment. The efficacy of losartan 50 mg/hydrochlorothiazide 12.5 mg titrated to losartan 100 mg/hydrochlorothiazide 25 mg was examined in 32 hypertensive patients with mild to moderate renal impairment who were treated for 12 weeks. Safety was assessed in both studies by the incidence of adverse experiences. After 7 days of treatment, the AUC for losartan, E‐3174, and hydrochlorothiazide was slightly higher in patients with mild to moderate renal impairment, but the reduction in blood pressure (BP) after 7 days was not different between the two groups. The final (week 12) mean reductions in trough sitting diastolic and systolic BP were 15.0 ± 7.1 mmHg (p < 0.01) and 20.8 ± 16.7 mmHg (p < 0.01), respectively. There were no observed increases in drug‐related adverse experiences in either study. Overall, the combination of losartan/hydrochlorothiazide was effective in lowering blood pressure and was well tolerated in patients with mild to moderate renal impairment.
The Journal of Infectious Diseases | 2018
Suzanne M. Garland; Punnee Pitisuttithum; Hys Ngan; C H Cho; Chuan-Mo Lee; Chi-Lin Chen; Yuh Cheng Yang; Tang-Yuan Chu; N F Twu; R Samakoses; Y Takeuchi; Tak-Hong Cheung; S C Kim; Li-Min Huang; B G Kim; Y T Kim; K H Kim; Y S Song; S Lalwani; J H Kang; M Sakamoto; H S Ryu; Neerja Bhatla; H Yoshikawa; M C Ellison; S R Han; Erin Moeller; S Murata; Michael Ritter; M Sawata
The 9vHPV vaccine was efficacious, immunogenic, and well-tolerated in Asian participants from 2 international, randomized clinical trials. Data support 9vHPV vaccination programs in Asia.
Papillomavirus Research | 2017
Ángela María Ruiz-Sternberg; Edson D. Moreira; Jaime Alberto Restrepo; Eduardo Lazcano-Ponce; Robinson Cabello; Arnaldo Silva; Rosires Pereira de Andrade; Francisco Revollo; Santos Uscanga; Alejandro Victoria; Ana María Guevara; Joaquin Luna; Manuel Plata; Claudia Nossa Dominguez; Edison Natal Fedrizzi; Eugenio Suarez; Julio C. Reina; Misoo C. Ellison; Erin Moeller; Michael Ritter; Christine Shields; Miguel Cashat; Gonzalo Perez; Alain Luxembourg
Background A 9-valent human papillomavirus (HPV6/11/16/18/31/33/45/52/58; 9vHPV) vaccine was developed to expand coverage of the previously developed quadrivalent (HPV6/11/16/18; qHPV) vaccine. Methods Efficacy, immunogenicity, and safety outcomes were assessed in Latin American participants enrolled in 2 international studies of the 9vHPV vaccine, including a randomized, double-blinded, controlled with qHPV vaccine, efficacy, immunogenicity, and safety study in young women aged 16–26 years, and an immunogenicity and safety study in girls and boys aged 9–15 years. Participants (N=5312) received vaccination at Day 1, Month 2, and Month 6. Gynecological swabs were collected regularly in young women for cytological and HPV DNA testing. Serum was analyzed for HPV antibodies in all participants. Adverse events (AEs) were also monitored in all participants. Results The 9vHPV vaccine prevented HPV 31-, 33-, 45-, 52-, and 58-related high-grade cervical, vulvar, and vaginal dysplasia with 92.3% efficacy (95% confidence interval 54.4, 99.6). Anti-HPV6, 11, 16, and 18 geometric mean titers at Month 7 were similar in the 9vHPV and qHPV vaccination groups. Anti-HPV antibody responses following vaccination were higher among girls and boys than in young women. Most (>99%) 9vHPV vaccine recipients seroconverted for all 9 HPV types at Month 7. Antibody responses to the 9 HPV types persisted over 5 years. The most common AEs were injection-site related, mostly of mild to moderate intensity. Conclusions The 9vHPV vaccine is efficacious, immunogenic, and well tolerated in Latin American young women, girls, and boys. These data support 9vHPV vaccination programs in Latin America, a region with substantial cervical cancer burden.