Dan Apter
University of Helsinki
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The Lancet | 2009
Jorma Paavonen; Paulo Naud; Jorge Salmerón; Cosette M. Wheeler; Song-Nan Chow; Dan Apter; Henry C Kitchener; Xavier Castellsagué; Júlio César Teixeira; S.R. Skinner; J Hedrick; Unnop Jaisamrarn; Genara Limson; Suzanne M. Garland; Anne Szarewski; Barbara Romanowski; Fred Y. Aoki; Tino F. Schwarz; Willy Poppe; Francesc Bosch; David Jenkins; Karin Hardt; Toufik Zahaf; Dominique Descamps; Frank Struyf; Matti Lehtinen; Gary Dubin
BACKGROUND The human papillomavirus (HPV)-16/18 AS04-adjuvanted vaccine was immunogenic, generally well tolerated, and effective against HPV-16 or HPV-18 infections, and associated precancerous lesions in an event-triggered interim analysis of the phase III randomised, double-blind, controlled PApilloma TRIal against Cancer In young Adults (PATRICIA). We now assess the vaccine efficacy in the final event-driven analysis. METHODS Women (15-25 years) were vaccinated at months 0, 1, and 6. Analyses were done in the according-to-protocol cohort for efficacy (ATP-E; vaccine, n=8093; control, n=8069), total vaccinated cohort (TVC, included all women receiving at least one vaccine dose, regardless of their baseline HPV status; represents the general population, including those who are sexually active; vaccine, n=9319; control, n=9325), and TVC-naive (no evidence of oncogenic HPV infection at baseline; represents women before sexual debut; vaccine, n=5822; control, n=5819). The primary endpoint was to assess vaccine efficacy against cervical intraepithelial neoplasia 2+ (CIN2+) that was associated with HPV-16 or HPV-18 in women who were seronegative at baseline, and DNA negative at baseline and month 6 for the corresponding type (ATP-E). This trial is registered with ClinicalTrials.gov, number NCT00122681. FINDINGS Mean follow-up was 34.9 months (SD 6.4) after the third dose. Vaccine efficacy against CIN2+ associated with HPV-16/18 was 92.9% (96.1% CI 79.9-98.3) in the primary analysis and 98.1% (88.4-100) in an analysis in which probable causality to HPV type was assigned in lesions infected with multiple oncogenic types (ATP-E cohort). Vaccine efficacy against CIN2+ irrespective of HPV DNA in lesions was 30.4% (16.4-42.1) in the TVC and 70.2% (54.7-80.9) in the TVC-naive. Corresponding values against CIN3+ were 33.4% (9.1-51.5) in the TVC and 87.0% (54.9-97.7) in the TVC-naive. Vaccine efficacy against CIN2+ associated with 12 non-vaccine oncogenic types was 54.0% (34.0-68.4; ATP-E). Individual cross-protection against CIN2+ associated with HPV-31, HPV-33, and HPV-45 was seen in the TVC. INTERPRETATION The HPV-16/18 AS04-adjuvanted vaccine showed high efficacy against CIN2+ associated with HPV-16/18 and non-vaccine oncogenic HPV types and substantial overall effect in cohorts that are relevant to universal mass vaccination and catch-up programmes. FUNDING GlaxoSmithKline Biologicals.
The Lancet | 2007
Jorma Paavonen; David Jenkins; F. Xavier Bosch; Paulo Naud; Jorge Salmerón; Cosette M. Wheeler; Song Nan Chow; Dan Apter; Henry C Kitchener; Xavier Castellsagué; Newton Sérgio de Carvalho; S. Rachel Skinner; Diane M. Harper; J Hedrick; Unnop Jaisamrarn; Genara Limson; Marc Dionne; Wim Quint; Bart Spiessens; Pascal Peeters; Frank Struyf; Susan L. Wieting; Matti Lehtinen; Gary Dubin
BACKGROUND The aim of this interim analysis of a large, international phase III study was to assess the efficacy of an AS04 adjuvanted L1 virus-like-particle prophylactic candidate vaccine against infection with human papillomavirus (HPV) types 16 and 18 in young women. METHODS 18,644 women aged 15-25 years were randomly assigned to receive either HPV16/18 vaccine (n=9319) or hepatitis A vaccine (n=9325) at 0, 1, and 6 months. Of these women, 88 were excluded because of high-grade cytology and 31 for missing cytology results. Thus, 9258 women received the HPV16/18 vaccine and 9267 received the control vaccine in the total vaccinated cohort for efficacy, which included women who had prevalent oncogenic HPV infections, often with several HPV types, as well as low-grade cytological abnormalities at study entry and who received at least one vaccine dose. We assessed cervical cytology and subsequent biopsy for 14 oncogenic HPV types by PCR. The primary endpoint--vaccine efficacy against cervical intraepithelial neoplasia (CIN) 2+ associated with HPV16 or HPV18--was assessed in women who were seronegative and DNA negative for the corresponding vaccine type at baseline (month 0) and allowed inclusion of lesions with several oncogenic HPV types. This interim event-defined analysis was triggered when at least 23 cases of CIN2+ with HPV16 or HPV18 DNA in the lesion were detected in the total vaccinated cohort for efficacy. Analyses were done on a modified intention-to-treat basis. This trial is registered with the US National Institutes of Health clinical trial registry, number NCT00122681. FINDINGS Mean length of follow-up for women in the primary analysis for efficacy at the time of the interim analysis was 14.8 (SD 4.9) months. Two cases of CIN2+ associated with HPV16 or HPV18 DNA were seen in the HPV16/18 vaccine group; 21 were recorded in the control group. Of the 23 cases, 14 (two in the HPV16/18 vaccine group, 12 in the control group) contained several oncogenic HPV types. Vaccine efficacy against CIN2+ containing HPV16/18 DNA was 90.4% (97.9% CI 53.4-99.3; p<0.0001). No clinically meaningful differences were noted in safety outcomes between the study groups. INTERPRETATION The adjuvanted HPV16/18 vaccine showed prophylactic efficacy against CIN2+ associated with HPV16 or HPV18 and thus could be used for cervical cancer prevention.
The Lancet | 2002
Helena von Hertzen; Gilda Piaggio; Alexandre Peregoudov; Juhong Ding; Junling Chen; Si Song; Gyorgy Bartfai; Ernest Hung Yu Ng; Kristina Gemzell-Danielsson; Amindavaa Oyunbileg; Shangchun Wu; Weiyu Cheng; Frank Lüdicke; Alenka Pretnar-Darovec; Rosemary Kirkman; Suneeta Mittal; Archil Khomassuridze; Dan Apter
BACKGROUND A single 10 mg dose of mifepristone, and two 0.75 mg doses of levonorgestrel 12 h apart, are effective for emergency contraception. Because no studies had compared the efficacies of both compounds, or investigated a single dose of 1.5 mg levonorgestrel, we undertook this three-arm trial. METHODS We did a randomised, double-blind trial in 15 family-planning clinics in 10 countries. We randomly assigned 4136 healthy women with regular menstrual cycles, who requested emergency contraception within 120 h of one unprotected coitus, to one of three regimens: 10 mg single-dose mifepristone; 1.5 mg single-dose levonorgestrel; or two doses of 0.75 mg levonorgestrel given 12 h apart. The primary outcome was unintended pregnancy; other outcomes were side-effects and timing of next menstruation. Analysis was by intention to treat, but we did exclude some patients from the final analyses. FINDINGS Of 4071 women with known outcome, pregnancy rates were 1.5% (21/1359) in those given mifepristone, 1.5% (20/1356) in those assigned single-dose levonorgestrel, and 1.8% (24/1356) in women assigned two-dose levonorgestrel. These proportions did not differ significantly (p=0.83). The relative risk of pregnancy for single-dose levonorgestrel compared with two-dose levonorgestrel was 0.83 (95% CI 0.46-1.50), and that for levonorgestrel (the two regimens combined) compared with mifepristone, 1.05 (0.63-1.76). Side-effects were mild and did not differ greatly between groups, and most women menstruated within 2 days of the expected date. Women who took levonorgestrel had earlier menses than did those who took mifepristone. INTERPRETATION The three regimens studied are very efficacious for emergency contraception and prevent a high proportion of pregnancies if taken within 5 days of unprotected coitus. Mifepristone and levonorgestrel do not differ in efficacy. A 1.5 mg single levonorgestrel dose can substitute two 0.75 mg doses 12 h apart.
Lancet Oncology | 2012
Cosette M. Wheeler; Xavier Castellsagué; Suzanne M. Garland; Anne Szarewski; Jorma Paavonen; Paulo Naud; Jorge Salmerón; Song Nan Chow; Dan Apter; Henry C Kitchener; Júlio César Teixeira; S. Rachel Skinner; Unnop Jaisamrarn; Genara Limson; Barbara Romanowski; Fred Y. Aoki; Tino F. Schwarz; Willy Poppe; F. Xavier Bosch; Diane M. Harper; Warner K. Huh; Karin Hardt; Toufik Zahaf; Dominique Descamps; Frank Struyf; Gary Dubin; Matti Lehtinen
BACKGROUND We evaluated the efficacy of the human papillomavirus HPV-16/18 AS04-adjuvanted vaccine against non-vaccine oncogenic HPV types in the end-of-study analysis after 4 years of follow-up in PATRICIA (PApilloma TRIal against Cancer In young Adults). METHODS Healthy women aged 15-25 years with no more than six lifetime sexual partners were included in PATRICIA irrespective of their baseline HPV DNA status, HPV-16 or HPV-18 serostatus, or cytology. Women were randomly assigned (1:1) to HPV-16/18 vaccine or a control hepatitis A vaccine, via an internet-based central randomisation system using a minimisation algorithm to account for age ranges and study sites. The study was double-blind. The primary endpoint of PATRICIA has been reported previously; the present analysis evaluates cross-protective vaccine efficacy against non-vaccine oncogenic HPV types in the end-of-study analysis. Analyses were done for three cohorts: the according-to-protocol cohort for efficacy (ATP-E; vaccine n=8067, control n=8047), total vaccinated HPV-naive cohort (TVC-naive; no evidence of infection with 14 oncogenic HPV types at baseline, approximating young adolescents before sexual debut; vaccine n=5824, control n=5820), and the total vaccinated cohort (TVC; all women who received at least one vaccine dose, approximating catch-up populations that include sexually active women; vaccine n=9319, control=9325). Vaccine efficacy was evaluated against 6-month persistent infection, cervical intraepithelial neoplasia grade 2 or greater (CIN2+) associated with 12 non-vaccine HPV types (individually or as composite endpoints), and CIN3+ associated with the composite of 12 non-vaccine HPV types. This study is registered with ClinicalTrials.gov, number NCT00122681. FINDINGS Consistent vaccine efficacy against persistent infection and CIN2+ (with or without HPV-16/18 co-infection) was seen across cohorts for HPV-33, HPV-31, HPV-45, and HPV-51. In the most conservative analysis of vaccine efficacy against CIN2+, where all cases co-infected with HPV-16/18 were removed, vaccine efficacy was noted for HPV-33 in all cohorts, and for HPV-31 in the ATP-E and TVC-naive. Vaccine efficacy against CIN2+ associated with the composite of 12 non-vaccine HPV types (31, 33, 35, 39, 45, 51, 52, 56, 58, 59, 66, and 68), with or without HPV-16/18 co-infection, was 46·8% (95% CI 30·7-59·4) in the ATP-E, 56·2% (37·2-69·9) in the TVC-naive, and 34·2% (20·4-45·8) in the TVC. Corresponding values for CIN3+ were 73·8% (48·3-87·9), 91·4% (65·0-99·0), and 47·5% (22·8-64·8). INTERPRETATION Data from the end-of-study analysis of PATRICIA show cross-protective efficacy of the HPV-16/18 vaccine against four oncogenic non-vaccine HPV types-HPV-33, HPV-31, HPV-45, and HPV-51-in different trial cohorts representing diverse groups of women. FUNDING GlaxoSmithKline Biologicals.
Clinical Endocrinology | 1980
Dan Apter
Pubertal development of 200 normal girls, 7–17 years of age, was investigated in a partly longitudinal manner with two examinations 1·5 years apart. Samples from postmenarchal girls were taken on days 6–9 and 20–23 of the menstrual cycle. Serum pregnenolone, progesterone, 17‐hydroxyprogesterone, dehydroepiandrosterone, androstenedione, testosterone, 5α‐dihydrotestosterone, androsterone, oestradiol and cortisol as well as ACTH, FSH, LH and prolactin were measured radioimmunologically and were related to bone age, breast and pubic hair developmental stages, and gynaecological age. In the samples of premenarchal girls as well as at the follicular phase of postmenarchal girls the concentration of all the steroids increased with age. Of all the steroids measured, serum dehydroepiandrosterone and pregnenolone displayed the earliest increase, from the youngest age group of 7·5 years onwards. Serum oestradiol, testosterone and androstenedione increased rapidly from the bone age group of 9·5 years (subjects 9·0–9·9 years of age) onwards, in close association with the appearance of the first physical signs of puberty. A marked increase in these three steroids continued until 13·5 years, the age at which menarche took place. Menarche was followed by a plateau of 1–2 years duration and then a second increase took place up to the two oldest age groups (17·5 and 18·5 years bone age), a trend seen in the follicular phase levels of all the steroids measured. The 5α‐dihydrotestosterone/testosterone ratio decreased with increasing testosterone concentration. Serum oestradiol, testosterone, androstenedione, dehydroepiandrosterone and FSH showed no overlapping in the 2·5–97·5% range of concentrations and androsterone and LH in the 16–84% range between pre‐pubertal and postmenarchal subjects. Pregnenolone, progesterone, 17‐hydroxyprogesterone, 5α‐dihydrotestosterone, cortisol, ACTH and prolactin overlapped even in the 16–84% range between these two groups of subjects. In postmenarchal girls, about 80% of the cycles were anovulatory in the first year after menarche, 50% in the third and 10% in the sixth year. The background of the majority of the anovulatory cycles seems to be a physiological variant of the pattern seen in the polycystic ovary syndrome: the levels of testosterone, androstenedione and LH were increased in anovulatory cycles compared to ovulatory ones.
Journal of Steroid Biochemistry | 1984
R. Vihko; Dan Apter
An initial group of 200 girls, 7-17 years old, was investigated longitudinally 4 times at 1.5-, 1.5- and 5-year intervals. The present study gives information of the impact of early menarche, a risk factor for breast cancer, on some physical and endocrine characteristics in these subjects. The frequency of ovulation depended significantly on both the time since menarche and the age at menarche. Early menarche was associated with early onset of ovulatory cycles. Even in early puberty, before menarche, the subjects who displayed early menarche during follow-up had higher serum FSH and estradiol concentrations than the girls whose menarche took place after the age of 13.0 years. Adrenal androgen secretion (dehydroepiandrosterone) was not influenced by age at menarche but it increased, as expected, on the basis of chronological age. The group with early menarche was characterized by high circulating estradiol concentrations also after menarche, even in the oldest subjects so far studied, 17-25 years of chronological age. At these ages, the differences in the frequencies of ovulatory cycles were disappearing between the groups formed on the basis of age at menarche. The present findings in pre- and postmenarcheal subjects suggest that the increased risk of breast cancer associated with early menarche is created over several years of exposure to high-level estrogen stimulus.
PLOS ONE | 2013
Unnop Jaisamrarn; Xavier Castellsagué; Suzanne M. Garland; Paulo Naud; Johanna Palmroth; Maria Rowena Del Rosario-Raymundo; Cosette M. Wheeler; Jorge Salmerón; Song-Nan Chow; Dan Apter; Júlio César Teixeira; S. Rachel Skinner; J Hedrick; Anne Szarewski; Barbara Romanowski; Fred Y. Aoki; Tino F. Schwarz; Willy Poppe; F. Xavier Bosch; Newton Sérgio de Carvalho; Maria Julieta V Germar; Klaus Peters; Jorma Paavonen; Marie-Cécile Bozonnat; Dominique Descamps; Frank Struyf; Gary Dubin; Dominique Rosillon; Laurence Baril
Background The control arm of PATRICIA (PApillomaTRIal against Cancer In young Adults, NCT00122681) was used to investigate the risk of progression from cervical HPV infection to cervical intraepithelial neoplasia (CIN) or clearance of infection, and associated determinants. Methods and Findings Women aged 15-25 years were enrolled. A 6-month persistent HPV infection (6MPI) was defined as detection of the same HPV type at two consecutive evaluations over 6 months and clearance as ≥2 type-specific HPV negative samples taken at two consecutive intervals of approximately 6 months following a positive sample. The primary endpoint was CIN grade 2 or greater (CIN2+) associated with the same HPV type as a 6MPI. Secondary endpoints were CIN1+/CIN3+ associated with the same HPV type as a 6MPI; CIN1+/CIN2+/CIN3+ associated with an infection of any duration; and clearance of infection. The analyses included 4825 women with 16,785 infections (3363 womenwith 6902 6MPIs). Risk of developing a CIN1+/CIN2+/CIN3+ associated with same HPV type as a 6MPI varied with HPV type and was significantly higher for oncogenic versus non-oncogenic types. Hazard ratios for development of CIN2+ were 10.44 (95% CI: 6.96-15.65), 9.65 (5.97-15.60), 5.68 (3.50-9.21), 5.38 (2.87-10.06) and 3.87 (2.38-6.30) for HPV-16, HPV-33, HPV-31, HPV-45 and HPV-18, respectively. HPV-16 or HPV-33 6MPIs had ~25-fold higher risk for progression to CIN3+. Previous or concomitant HPV infection or CIN1+ associated with a different HPV type increased risk. Of the different oncogenic HPV types, HPV-16 and HPV-31 infections were least likely to clear. Conclusions Cervical infections with oncogenic HPV types increased the risk of CIN2+ and CIN3+. Previous or concomitant infection or CIN1+ also increased the risk. HPV-16 and HPV-33 have by far the highest risk of progression to CIN3+, and HPV-16 and HPV-31 have the lowest chance of clearance.
Journal of Steroid Biochemistry | 1974
Olli A. Jänne; Dan Apter; R. Vihko
Abstract A method for the determination of testosterone, progesterone and 17α-hydroxyprogesterone in 1–2 ml samples of male and female blood plasma is described. After extraction of the unconjugated steroids, they are chromatographed on a column of a highly lipophilic Sephadex derivative, hydroxyalkoxypropyi Sephadex, in light petroleum-chloroform, 95:5. The final measurement of the individual steroids is made by radioimmunoassay using dextran-coated charcoal in the separation of bound and unbound radioactivity. Using 1–2 ml plasma samples the limit of sensitivity for progesterone and testosterone determination was about 0.1 ng/ml and for 17α-hydroxyprogesterone about 0.15 ng/ml. The coefficients of variation in the determination of these steroids ranged from 7.9–15.4%. The blank values, obtained by analysis of quartz-distilled water by the method described, were negligible in the tesosterone and 17α-hydroxyprogesterone determinations. Values below 10 pg were sometimes observed in the progesterone analysis. Plasma concentrations of these three steroids in a group of females both in the follicular and luteal phase of the menstrual cycle and in connexion with the intake of oral contraceptive of the combination type are presented. In addition, values obtained in a group of normal males are also given. The concentration values can be obtained within two days of drawing the blood samples and one technician can analyze 20 plasma samples in a 5-day period.
International Journal of Cancer | 2012
Anne Szarewski; Willy Poppe; S.R. Skinner; Cosette M. Wheeler; Jorma Paavonen; Paulo Naud; Jorge Salmerón; Song-Nan Chow; Dan Apter; Henry C Kitchener; Xavier Castellsagué; Júlio César Teixeira; J Hedrick; Unnop Jaisamrarn; Genara Limson; Suzanne M. Garland; Barbara Romanowski; Fred Y. Aoki; Tino F. Schwarz; Francesc Bosch; Diane M. Harper; Karin Hardt; Toufik Zahaf; Dominique Descamps; Frank Struyf; Matti Lehtinen; Gary Dubin
In the Phase III PATRICIA study (NCT00122681), the human papillomavirus (HPV)‐16/18 AS04‐adjuvanted vaccine (Cervarix®, GlaxoSmithKline Biologicals) was highly efficacious against HPV‐16/18 infections and precancerous lesions in women HPV‐16/18 deoxyribose nucleic acid (DNA) negative and seronegative at baseline. We present further data on vaccine efficacy (VE) against HPV‐16/18 in the total vaccinated cohort including women who may have been exposed to HPV‐16/18 infection before vaccination. In women with no evidence of current or previous HPV‐16/18 infection (DNA negative and seronegative), VE was 90.3% (96.1% confidence interval: 87.3–92.6) against 6‐month persistent infection (PI), 91.9% (84.6–96.2) against cervical intraepithelial neoplasia (CIN)1+ and 94.6% (86.3–98.4) against CIN2+ [97.7% (91.1–99.8) when using the HPV type assignment algorithm (TAA)]. In women HPV‐16/18 DNA negative but with serological evidence of previous HPV‐16/18 infection (seropositive), VE was 72.3% (53.0–84.5) against 6‐month PI, 67.2% (10.9–89.9) against CIN1+, and 68.8% (−28.3–95.0) against CIN2+ [88.5% (10.8–99.8) when using TAA]. In women with no evidence of current HPV‐16/18 infection (DNA negative), regardless of their baseline HPV‐16/18 serological status, VE was 88.7% (85.7–91.1) against 6‐month PI, 89.1% (81.6–94.0) against CIN1+ and 92.4% (84.0–97.0) against CIN2+ [97.0% (90.6–99.5) when using TAA]. In women who were DNA positive for one vaccine type, the vaccine was efficacious against the other vaccine type. The vaccine did not impact the outcome of HPV‐16/18 infections present at the time of vaccination. Vaccination was generally well tolerated regardless of the womans HPV‐16/18 DNA or serological status at entry.
Obstetrics & Gynecology | 2013
Anita L. Nelson; Dan Apter; Brian Hauck; Thomas Schmelter; Sarah Rybowski; K. Rosen; Kristina Gemzell-Danielsson
OBJECTIVE: To evaluate the efficacy and safety of two low-dose levonorgestrel intrauterine contraceptive systems. METHODS: Nulliparous and parous women aged 18−35 years with regular menstrual cycles (21−35 days) requesting contraception were randomized to 3 years of treatment with one of two levonorgestrel intrauterine contraceptive systems: 13.5 mg total content or 19.5 mg total content. The primary outcome was the pregnancy rate, calculated as the Pearl Index. RESULTS: Overall, 1,432 and 1,452 women in the 13.5 mg intrauterine contraceptive system and 19.5 mg intrauterine contraceptive system groups, respectively, had a placement attempted and were included in the full analysis set to evaluate efficacy and safety. Mean (standard deviation) age was 27.1 (4.8) years; 39.2% were nulliparous. Over the 3-year study period, 0.33 pregnancies per 100 women-years (95% confidence interval [CI] 0.16–0.60) were observed with the 13.5 mg intrauterine contraceptive system compared with 0.31 per 100 women-years (95% CI 0.15–0.57) with the 19.5 mg intrauterine contraceptive system. Kaplan-Meier estimates for that period were 0.009 and 0.010, respectively. At least partial expulsions occurred in 4.56% and 3.58% and discontinuation rates resulting from a reported adverse event occurred in 21.9% and 19.1%, respectively. Ten of the 20 pregnancies were ectopic. Serious adverse events included six cases of pelvic inflammatory disease and one partial uterine perforation. CONCLUSIONS: Both lower-dose levonorgestrel intrauterine contraceptive systems were highly effective for 3 years of use and generally well tolerated. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov, www.clinicaltrials.gov, NCT00528112. LEVEL OF EVIDENCE: I