CONTRACEPTION
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`PRARMACOKIRRTIC STUDY OF DIFFRREXT DOSES OFDKPOPROVRRA K. Fotherby', S. Koetsawang* and M. Mathrubuthan? 'Royal Postgraduate Medical School, Ducane Road, London W12, hgland; 2 Siriraj Family Planning Research Unit, Siriraj Hospital, Bangkok, Thailand ABSTRACT Doses of DcpoProvera of 25, 50, 100 and 1SOmg were administered to four groups of women. The mean time for the return of follicular :and luteal activity increased with increasing dose of DcpoProvcra. Lutcal activity was suppressed for a longer period than follicular activity. Xone of the women receiving th- two higher doses of DepoProvera showed a return of lutenl function within 100 days of injection. The period for r\rhich medroxyprogesterone acetate (RP.1) was detectable in serum incrczsed v:ith increasing dose but the values for the 100 cand X5Omc; doses were not significantly different. Thcrc :sns :I signific.ant correlation bctleen the concentration of l;Pzl in blood and the return of follicular and luteal function. It is suggested that in the population studied,
`DepoProvern t-ould be as effective as the usual 15Omg dose and that injection of J'Cmn DepoProvera would provide a contraceptive effect for two months. The dose of &PA in the monthly injectable CycloProvera could be substantially reduced without loss of effectiveness. Accepted for publication October 9, 1980 NOVEMBER 1980VOL.22NO.5 527
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`1OOmg
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`Amneal Pharmaceuticals LLC v. Alkermes Pharma Ireland Limited
`IPR2018-00943
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`0.1
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`CONTRACEPTION
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`INTRODUCTION DepoProvera, a microcrystalline suspension of medroxyprogesterone acetate, has been widely used as an injectable contraceptive (1). The failure rate using an injection of 150 mg every 90 days is less than
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`per 100 women-years. Ho:,ever, a number of studies have shown that MPA may still be detectable in the circulation in many women for more than 90 days after injection of this dose and in some women WA was detectable for more than ?OO days after injection (2, 3, 4). This high circulating, level of WA leads to prolonged suppression of pituitary, -and hence ovarian, activity and is probably the cause of the high incidence of .amenorrhoea seen in women using DepoProvcra. Almost all of the phnrmacokinetic studies of DepoProvera have been carried out in Caucasi,an women and it mipht be expected that in other ethnic groups, usually of lower body weipht, the dose of DepoProvera could be considerably reduced without any loss of efficacy. No information is available on levels of lipA in blood after administration of doses of DepoProvcra lower than 150 mg or the effect of lower doses on ovulation. In the present study, Croups of Thai women were treated with doses of DepoProvera of 25, 50, 100 <and 150 my and the effect of these doses on ovulation suppression and on menstruation was determined and correlated with the levels of PIPA in blood. SUBJECTS AND METHODS Volunteer subjects were obtained from women attending a Thai. Fzmily Planning clinic who had opted to use nn injectable contraceptive. The aim of the study was explained to the women and written consent for their participation was obtained. The women were between "4 <and 36 years in ape with regular menstrual cycles for six months preceding, entry into the trial. None had been pregnant within
`days or lactating within 60 days prior to admission into the trial. All subjects had a full clinical examination before entering the study and none had ".ny contraindications to the use of a steroidal contraceptive. Since the contraceptive efficacy of doses of DepoProvera below 150 mg could not be puaranteed, women using lower doses were advised to use a barrier method of contraception. Four groups each of five women were studied. The women were r.andomly allocated to these groups. The women in each group received 75, 50, 100 or 150 mg DepoProvera as a deep intramuscular injection in the gluteal region between days 4 and 6 of a menstrual cycle. Subjects were studied for one cycle prior to injection and up to six months after injection. Blood samples were taken twice weekly. Each subject was given a record card on which to record episodes of bleeding and the card was used also to indicate the days on which the subject was to attend for blood sampling. After sampling,the blood was alloved to clot at room temperature, then centrifuged and the serum removed. The serum was deep frozen and transported to London frozen in dry ice where each sample was analyscd by rsdioimmunonss.ay for the levels of mcdroxyproresteronc 528 NOVEMBER 1980VOL.22N0.5
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`120
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`Amneal Pharmaceuticals LLC v. Alkermes Pharma Ireland Limited
`IPR2018-00943
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`CONTRACEPTION
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`acetate (s), oestridiol and progesterone. Quetelet's index (weight in KS divided by square of height in mctres) was calculated
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`(6).
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`Details of the subjects enrolled in the trial are shown in Table I. There wx no simificant difference between the women in each of the four groups in respect of age, height <and body vreight. Two women in Group
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`50
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`77
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`59.6
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`and one each in Groups 100 2nd 1'0 had values for Qu?telet's index above the upper limit (74!units() of the 'dcsir_iDle range*(T). All subjects showed rise in the plasma oestrxdiol or progesterone levrls during the control cycle, indicating that ovulation had occurred. Effect of DepoProvera on ovarian fLmction The duration of the suppressive action of the various doses of DcpoProvcra on ovarian function as assessed by plasma levels of oestradiol and progesterone is indicated in Table I. A rise in the plasma oestradiol level greater than 150 pr]ml \<-a~ taken to indicate the presence of follicular activity and luteal activity was presumed to be present when the plasma progesterone level exceeded 3 ngfml. The mean time for the return of follicular function increased with increasing doses of DepoProvera and varied front 41.0 days in Group "5 to
`days in Group 100 and 110 days in Group 170. There was no si&ficant difference between Groups 35 and 50, 50 and 100 and 100 and 150 in the time required for the return of follicular activity. Hol.ever, there were significant differences in the return of follicular function between Groups 25 and 100 (P < O.OS), between Groups ?S and 120 (P < 0.01) and between Groups 50 and 150 (P c 0.05). Inhibition of follicular activity for more than 90 days occurred in all except one of the subjects in Group 150, in two subjects in Group 100 but in none in Groups ?5 and 50. In six subjects (A, E, F, L, 0 and U) the return of follicular activity was associated with a broad peak of elevated oestradiol levels extending over a period of 20 to 50 days. None of these peaks was associated with a rise in the plasma progesterone level. For eight subjects (B, G, H, K, N, P, S and V) the occasion on which follicular activity first returned was follol:ed by a rise in the plasma progesterone level indicating that ovulation occurred as soon as follicular function returned (Table I), whereas in the majority of subjects the first evidence of follicular function was not followed by a rise in the plasma progesterone level indicating that ovarian follicular activity returned some considerable time before luteal activity. This suppression of lute11 function was particularly lengthy in subjects receiving the two higher doses of DepoProvera. For these women, none shofccd a return of luteal activity within 100 days of injection whereas all except two
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`of
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`GrOtIpS
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`“5
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`the 10 women in Groups 7: and 50 shov:cd a return of luteal function within this time.. Thr differences between Groups 25 and 50 .and between Groups 100 and 150 in the time of return of luteal ftmction were not signific.ultly different, but there were significant differences between
`50 ‘and 100 (P c 0.05), between Groups Y-5 and 1:O (P < 0.01) and between Groups 50 and 150 (P < 0.01). NOVEMBER 1980VOL.22NO.S 529
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`Groups
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`AMN1086
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`RESULTS
`days in Group 50,
`-Lnd 100 (P < O.Ol), between
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`CONTRACEPTION Table I. Details of subjects receiving various doses of DepoProvera and changes in ovarian function. Subject Age (Y) Body wt(Kg) DMPA 25 mC A 36 B 35 C 25 D ?7 E 36 Mean 31.8 SD 5.4 DMPA 50 mp F ?? ._ _ C 29 H 31 J 30 K 09 Mean 30.," SD 1.7 DMPA 100 mg L 34 M 31 N "4 0 29 P 35 Mean 31.3 SD 3.9 DMPA 1.50 mg R 34 S 33 T 36 U 35 V 30 Mean 33.6 SD 2.3 53 162 62 166 59 158 57 158 47 157 51 159 61 151 60 160 65 147 53 150 65 156 46 153 SO 162 53 160 59 156 63 1% 56 153 62 161 48 157 45 149 Height (cm) Quetelet's index D.ays after injection for plasma oestradiol (E) or proccsterone (P) to show significant rise E P 30.2 36 27.5 50 23.6 "9 ?2.8 a9 19.1 6" 71.8 41.1 1.7 14.4 20.2 64 26.7 83 "OL' ‘. .I. 58 30.1 ;1 "3.6 59 24.8 59.6 ".7 15.6 81 53 > 50 81 108 74.6 Oq 8 3. 120 86 65 91 55 94.3 ?7.?. ?6.7 50 148 19.6 71 137 19.1 95 102 '0.7 57 148 "4.Y 112 l"3 ?2.1 77.0 131.6 3.3 26.0 19.5 36.6 119 155 23. 9 97 104 23.9 > 167 > 167 19.5 66 157 20.3 101 107 T3.1 110.0 136.6 2.4 37.1 27.5 530 NOVEMBER 1980VOL.22N0.5
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`AMN1086
`Amneal Pharmaceuticals LLC v. Alkermes Pharma Ireland Limited
`IPR2018-00943
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`CONTRACEPTION
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`For ei.;ht women follicular activity returned while b2PA was still detectable in blood but in no Woman did luteal function return until KP'h was undetect-ible. For the remaining ten woc!en (omitting subjects C and T), follicular activity returned betyreen 2 and :7 d~yys (me~x 20.2 days) aftrr strum EPA became undetectable whereas lute.11 function did not return until l4 to 107 days (nc.m r:4 days). T!w tine of return of ovxi,E function in relation to the uptake -and metabolism of De>oProvcra is sho!,n in Fir. 1. There V.JS a statistically significant correlation (P < 0.05) between the time after injection .Lt &ich scrnx S'A l_ev:ls became undetcctnble (Y) and the ti.iLl? of rcturr (X) o? follic~~ltr xnd lute21 activity. T!lc equation for the regressioil lint kth respect to folliculrtr activity c2s Y = 0.4_% + 53." and th>lLtt for luteal activity WAS y = 0.46X + 1;.&. Metabolism of medromrogesterone acetate ?:(>a~ v.~lues for the plz,sm,l concentr_d.tion o f r:PA of the four ,r.roups of ~romncn at varying tifles nfter injection <we show ir 3%:. n md other in?ormation rel,xting to the 7ietabolisn: of DepoProvcrx is sumxrised in Table II. The nean v,xluc for the hi:,hcst scr'Im? PTA conccntr-:tion detected It .*ny time after injection iccrexscd with increzisiny, doses OC D!!PA, but .AS shojn ti Table II, there wx a considerable variation in the individual values. ;,%ereas only two of the subjects in Groups 100 and 130 had levels less than 4 r&ml, only three of the women in Groups 15 and 50 had values higher thzn this. However, these results must be interpreted with caution since sariples were collected only lxicc weakly :tr.d the day on which the highest :!PF$ conccn- tration actu.llly occurred m.ty hav:: been rdssod. However, the dqs for which NP.1 was detectable in scrux, i.e., -1 concentration gcatcr thin 100 p&l, incrc-rscd :is the dose of DcpoProv?rQx a&&nist:?red incrcxcd up to 100 I!!?. &ltholl:_h thcrr VJ.S no signi!'icant diffcrzcc br:tbrcen the tr.0 107 pr doses or b-tceen the t!ro lli;h,Tr doses ix the nuxoer of days for b.IG.ch I!PS \!;s dctcclxble in the circuli:tion (IX,-.'), there :"3.s 1 st2tis- ticslly sipnificvlt difference bctt,een the two low-r doses compwcd \.G.th t!w t:;o hi:hcr does (F < 0.01). :,'bcn the plzsms. E~p.9 levels for each subjr-ct xrc plotted scmi- lofw-it!~xG.cally a,p,ainst tiw Lftcr in jection,.,pproximately str-li::ht lines were obt;tir.ed. As expected there was a highly signific&mt correlation beixeen the plasma 3Ph levels nnd time ,lfter injection in all subjects IS showr by the values for the correlation cocfricicnt R (T;tble II). The vah~cs for the slope of these regression lines is also shokn ii: Tlbl- II and rqrescnt the rate at which EPA was taken up from the injection site :md ,setabolised. If it is assumed that the rate of metabolisla of ?%'A in the subjects was similar and not dependent on the dose of DepoProvcra injected, then the value for the slop e is rcl;ted to the rate of upta!<e from the injection site. The higher values for the slope in subjects taking, the two lower doses indicate a relatively more rapid uptake than in subjects receiving the two higher doses. No.-ever, there :izs a considexxble between subjxt variation in the value for the slope *and the mean value for Group ?_5 was not significcintly different from that of Group I'O. The value for the constant B (Table II) which represents the plasma WA concentration assuming instantaneous distribution increased with the dose of DepoProvera injected but only the differences between the tvro lowest dose groups and Group 150 were statistically significant (P c 0.05).
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`NOVEMBER 1980 VOL. 22 NO. 5
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`Amneal Pharmaceuticals LLC v. Alkermes Pharma Ireland Limited
`IPR2018-00943
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`CONTRACEPTION
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`.
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`(116)
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`60 -
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`20
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`80
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`100
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`120
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`Days
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`after
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`injection
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`for
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`return
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`of ovarian
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`activity
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`Fig. 1. Time after injection of various doses of DepoProvera for return of follicular (M) and luteal (0 --0) fnction in relation to time required for disappearance of
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`HT’h
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`from blood. Solid and broken lines denote regression lines for follicular and luteal function respectively. 7000 5000 = $
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`1000
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`I I I , I I , I I 10 20 30 40 50 60 70 80 90 Days
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`injection
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`after
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`Fig. 2. (M), Hean serum MPA levels after injection of 25 mg (TV), 50 mg 100 mg (W) and 150 mg (W) DepoProvera. Each point is the mean of five samples. 532 NOVEMBER 1980VOL.22N0.5
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`AMN1086
`Amneal Pharmaceuticals LLC v. Alkermes Pharma Ireland Limited
`IPR2018-00943
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`CONTRACEPTION
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`TABLE II. Metabolism of MPA after injection of various doses of DepoProvrrn Subject DIE'A ? j n!r A B C D E Mean SD DMPA -70 my F G H J K Ikxn SD DMPA 100 rnc L M N 0 P Mean SD DMPA 150 rn~ R S T U V Mean SD Hichest MPA cone (w/d) Regression line Days MPA detectable Slope, (X10_') B R 2.12 116 ?.46 4 .; 7 "9 4.?9 1.09 > 50 I."9 1.63 39 3.06 I.?0 59 1.46 ".I? 44.6 y.65 1.4; 11.2 1.49 3.359 3.611 3.018 3.375 3.110 3."91 0 ""7 .* ._ .89 .91 .93 .92 .86 .90 .03 ?..C3 6;: 1.93 1.97 58 ? 3L( . . . 5.38 dl 2.70 6.06 59 ^ C? . _ 2 3.65 iI 1 T.10 3.9: jn.6 T.70 1.77 10.8 0.71 3.^9" .91 ;.f,75 .96 .:.614 .9,: 3.6~1 .91 3.rg .96 ;.i96 .9," 0.140 .O." 3.60 116 0.90 ?.4l( .88 7.v 71 1.9-Y 3.911 .97 8.36 60 7.61: 2.965 .96 > 8.00 61 2.44 3.966 .95 4.50 9.5 1.49 3.593 . 9; 6.37 80.6 1.89 3.770 .94 s.16 "4.3 0.70 0.73'2. .03 9.74 9.58 7.67 > 10.00 > 10.00 8.20 3.16 87 87 > 167 5: 6$ 9Y.O BC I .,. 1.43 3.894 .96 2.04 3.920 .97 0.46 3.?53 .78 3.51 4.189 .?8 ?.76 4.159 .98 3.04 3.883 .93 I.18 0.277 .09
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`NOVEMBER 1980 VOL. 22 NO. 5
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`Amneal Pharmaceuticals LLC v. Alkermes Pharma Ireland Limited
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`533
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`CONTRACEPTION
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`50
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`l
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`100 1.50 range 11-31 9-35 10-38 6-27 mean ?1 18 "1 16 Plean no. of episodes 3.0 2.4 7' _I
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`Kffect Of DepoProvera on bleeding pattern The effect of varying doses of DepoProvcra on the bleeding pattern during the 90 days after injection is sununariscd in Table III. There w%s a riide variation bet:rcen the different subjects ,and with the small number of women involvc~ none of the differences were signific,ant but as the dose of DepoProvern increased LIP to 100 mg, there was a tendency for the number of episodes of blreding to decrease and for the segment length to increase. Table III. Effcct'of DcpoProvera on bleeding pattern Group No. of days of bleeding 25
`_ 2.4 Segment length (days) mean S.D. 26.W.9 29.7f16.5 37.5*13.4 36.6f17.8 DISCUSSION There was a marked variation in each dose group in the return of ovarian function. For most subjects follicular activity, as indicated by the rise in serum oestradiol levels, returned earlier after injection than did luteal activity, as indicated by the rise in serum progesterone levels. Whether this rise in serum oestradiol levels was associated with ovulation and the possibility of a pregnancy ensuing is not known but appears unlikely. By analogy with women treated with low doses of gestagens,it is likely that formation of a corpus luteum occurs and that progesterone biosynthesis is inhibited (8). In some women, the return of follicular activity was associated with the secretion of large amounts of oestradiol over a long period of time, a phenomenon which also occurs in women treated with low doses of gestagens. There was a significant correlation between the time after injection for MPA to become undetect- able and the return of follicular and luteal function. In a present study, serum progesterone levels did not increase in any woman until serum WA had become undetectable. Luteal function was suppressed for more than 100 days in all of the women receiving the two higher doses of DepoProvera and in two of the women receiving the lower doses. A number of previous studies have shown that in some women BPA is detectable in serum for 200 or more days after injection of 150 mg DepoProvera (2,3,4). In this respect the five women in the present study receiving the highest dose of DepoProvera were atypical in that in only one 534 NOVEMBER
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`1980
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`AMN1086
`Amneal Pharmaceuticals LLC v. Alkermes Pharma Ireland Limited
`IPR2018-00943
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`VOL.22N0.5
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`CONTRACEPTION subject was MPA detectable for more than 100 days. In a further two subjects,MPA was detectable for about 90 days, the usual injection interval for this dose,and in the rem sining two, MPA became undetectable by 55 and 64 days after injection. In the latter two subjects, the initial MPA concentration was very high suggesting that in these subjects there was an initial very rapid uptake of the steroid from the injection site. In spite of this however, luteal function was still inhibited for more than the 9O-day injection interval. Since only five subjects were included in each dose group,the results obtained must be regarded as preliminary and interpreted with caution. However, in the two higher dose groups the fact that there was no difference with respect to the uptake and metabolism of DepoProvera, the length of time for which ovarian function was suppressed Rnd the effect upon the bleeding pattern,Fould suggest that in the population studied a dose of 100 mg DepoProvera would be as effective over a 9O-day period as the usual150 mg dose. The results might also suarrest that a dose of 75 ma would have an anti-fertility effect for this period of time. Although the mean time for the ret&n of luteal activity in women receiving 50 mg DepoProvera was more than 90 days,there was a marked variation between subjects. However,the results obtained suggest that a dose of 50 mg DepoProvera might be suitable as a two- monthly injectable formulation. CycloProvera, a formulation consisting of 2j mg, MPA and 5 mg oestra- diol cypionate, is used in some countries as a montly injectable formula- tion (9,lO). In a study of Thai women who had been using this formulation for a number of years, it was shown that the plasma levels of MPA 28 days after injection were significantly higher in women who had received over 20 injections of CycloProvera than in women who had received a single injection (11) and it was suggested that the dose of MPA in CycloProvera could be reduced. This suggestion receives support from the present results; after injection of 2.5 mg DepoProvera, WA was detectable in plasma for up to 59 days and in no woman did luteal function return until 53 days after injection. AcKNOKCEDGEMEXTS This work was supported by a grant from the Special Programme of Research in Human Reproduction of the World Health Organization. Ve are grateful to Dr. Iris Reis and 3.L Coussey for the oestradiol and progesterone assays. NOVEMBER 1980VOL.22NO.5 535
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`IPR2018-00943
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`Kirton, K.T. and Cornette, J.C. Return of ovulatory cyclicity following an intramuscular injection of medroq-progesterone acetate. Contraception 10: 39-45 (1974). Ortiz, A., Hiroi, M., Stanczyk, F.Z., Goebelsmann, U. and Mishell, D.R. Serum; MPA concentrations and ovarian function follo+ing intramuscular injection of DepoProvera. J.Clin.Endocrinol. lietab. 44: 3:-3e
`Benagiano, G., Fotherby, K., Saxena, B.K., Schrimanker, K., Hingorani, V., Takker, I)., Diczfalusy, E. and Landgren, B.M. A preliminary pharmacokinetic and pharmacodynamic evaluation of Depo-medroxyprogesterone acetate and norethisterone oenanthate. Fertility and Sterility (1980) In press. Shrimanker, K., Saxena, B.N. and Fotherby, K. A radioimmunoassay for serum medroxyprogesterone acetate. J.Steroid Biochem. 9:
`T. and Lowe, C.R. Indices of obesity derived from body weight and height. Br.J.Prev.Soc.Ned. 21: 12"-128 (i967). Garrow, J.S. Weight penalties. Brit.lled.J. 2: 1171-1172 (1979). Fothcrby, i.. Low doses of gestagcns as fertility regulating agents. In: Regulation of Buman Fertility. E. Diczfalusy, editor. Scriptor, Copenhagen,
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`(1975).
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`X9-362
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`283-321.
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`1977,
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`11. PEFEREKCES Rinehart, 1;. and Uinter, J. Injectables and implants. Population Reports, Series Ii, Bo. 1, Kl-Kl6
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`CONTRACEPTION
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`3.
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`1. ? .A.
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`4. r 3.
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`6.
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`7.
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`a.
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`(1977).
`
`(1978).
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`Khosla,
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`Benagiano, G. Long-acting systemic contraceptives. In: Regulation of Hunan Fertility, E. Diccfalusy, editor. Scriptor, Copenhagen,
`1977,
`3?3-360.
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`10.
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`Toppozada, 1;. The clinical use of monthly injectable contraceptive preparations. Obstetrics Gynaecolo&y Survey. 32:
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`Koetsawang, S., Shrimankcr, K. and Fothcrby, K. Blood levels of medroxyprogesterone acetate after multiple
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`335-347
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`(1977)
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`injeCtiOnS
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`Of
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`Depoprovera or Cycloprovera. Contraception 20: l-4 (1979).
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`9.
`pp
`pp
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