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UNDERSTANDING DOWN REGULATION GnRH Agonists and Antagonists In ART

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UNDERSTANDING DOWN REGULATION GnRH Agonists and Antagonists In ART by Dr. Narendra Malhotra, Dr. Jaideep Malhotra

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UNDERSTANDING DOWN REGULATION GnRH Agonists and Antagonists In ART

  1. 1. narendra malhotra jaideep malhotra www.malhotrahospitals.com www.rainbowhospitals.org UNDERSTANDING DOWN REGULATION GnRH Agonists and Antagonists In ART
  2. 2. • The IVF story is today more than 35 years old • Acceptance to this method of procreation is now widely acceptable • More than 4.3million babies have been born by IVF • Protocols have been changing everyday for better patient comfort and convenience The IVF Story 2010 Congrats Bob Edwards For the Nobel prize 2010 And Indira Hinduja for Padamshree 2011
  3. 3. CHANGING APPROACH YESTERDAY TODAY TOMORROW CONVENTIONAL MILD/MINIMAL INDIVIUALISED More Oocytes Supraphysiological E2 Agonist protocols More embryos/OHSS Multiple pregnancies Cryopreservation Less Oocytes Optimal E2 Antagonist protocols No OHSS No multiple pregnancies Lower cost Optimal Oocytes/Embryos No OHSS No Multiple pregnancies Lower cost PATIENT FRIENDLY
  4. 4. Problems of Ovarian Stimulation • Poor responders • Hyper responders: OHSS & multiple pregnancies • Premature LH surge
  5. 5. Controlled ovarian stimulation with recombinant FSH and GnRHa has been the key factor in success of IVF. Orvieto.R 2004
  6. 6. agonists • The main aim of introducing the agonists to IVF protocol was to prevent the premature LH surge TO START USING AGONISTS FOR ART WE NEED TO UNDERSTAND DOWNREGULATION
  7. 7. understanding downregulation
  8. 8. GnRH • is produced & secreted by a group of neurons located in the arcuate nucleus of medial basal hypothalamus & preoptic area of ventral hypothalamus. • These molecules are transported to pituitary by intricate network of capillaries.
  9. 9. GnRH • Is a decapeptide with a short half life. • regulates trophic function of anterior pituitary gland. • Plays a key role in functioning of hypothalamic-pituitary axis • Regulates production & release of both LH & FSH in the gonadotrophs of ant. Pituitary.
  10. 10. PHYSIOLOGY OF GnRH ACTION • Gonadotrophs of ant.pituitary release FSH and LH rhythmically in response to rhythmic release of GnRH. • This secretion of GnRH is governed by GnRH pulse generators which resides in mediobasal hypothalamus. • This pulse generator is operative during fetal life and in early infancy but is suppressed by intrinsic inhibitory control
  11. 11. Puberty starts when GnRH pulse generator is released from suppressive effects of gonadostats at around 8.5 –12.5 yrs in girls and 9.5-13.5 yrs in boys.
  12. 12. • GnRH secretions are negatively modulated by gonadal steroids. • However under certain circumstances estradiol can have positive influence,on GnRH secretion like prior to ovulation. • Prolonged strenuous exercise and severe weight loss can inhibit GnRH secretion.
  13. 13. The number of receptor in the membrane of gonadotrophs change with altered physiological conditions and are subjected to up & down regulation.
  14. 14. ••It is possible to readily synthesise GnRH agonists by using solid peptide synthesis. It is possible to introduce amino acid substitution to prolong the half life . Position 6 of amino acid sequence is important for inactivation. 2 and 3 for gonadotropin release 1,6 and 10 for binding 1 2 3 4 5 6 7 8 9 10 GnRH shows two phases with half lives of 2-8 mins for fast and 15-60 mins for slower phase
  15. 15. GnRH AGONISTS SYNTHETIC AGONISTS • INCREASE STABILITY AND BINDING AFFINITY TO ITS RECEPTORS. • 100-200 TIMES HIGHER. What is the need to synthesise agonists?
  16. 16. GnRH agonists • First synthesised in 1972 • produced by altering the amino acids at position 6 and /or 10,resulting in compounds with higher affinity for the GnRH receptors and a long half-life due to their resistance to cleavage by endopeptidases & reduced susceptibility to enzymatic degradation • Half life is of few hrs.
  17. 17. • It is possible to readily synthesise GnRH agonists by using solid peptide synthesis,also possible to introduce amino acid substitution to prolong the half life . • Multiple amino acid substitution permits synthesis of antagonists.which bind to GnRH receptors and provide competitive block for naturally synthesised GnRH.
  18. 18. GnRH Analogs: Historical Perspective • Prior to use of GnRH analogs, up to 20% of treatment cycles were cancelled due to spontaneous LH surges that interferes with follicular development1 • GnRH agonists were the first GnRH analogs available for suppression of LH secretion1 – Clinical pregnancy rate was significantly improved – Decreased the likelihood of cycle cancellation 1. Hughes et al. Fertil Steril. 1992;58:888. 2. Devroey et al. Hum Reprod. 2009;24:764.
  19. 19. AGONISTS Seven approved analogues are; • Buserelin • Leuprorelin • Goserelin • Histrelin • Deslorelin • Nafarelin • Triptorelin
  20. 20. GnRH AGONISTS Agonist Structure Route Dose, mg Potency GnRH =1 Leuprorelin D-Leu6, Subcutaneous 0.5-1.0 15-100 Pro9-NHET intramuscular, 3.75-7.5* depot Buserelin D-Ser(Bu)6, Subcutaneous 0.2 100 Pro9-NHET intranasal 0.9-1.2 Histrelin D-His(BZ)6, Subcutaneous 0.1 100 Pro9-NHET Nafarelin D-[Na(2)6] Intranasal 0.4-0.8 200 Triptorelin D-Trp6 Intramuscular, 2-4* 100 Polymer Goserelin D-Ser(tBu)6 Subcutaneous, 3.6* 230 aza-Gly10 implant
  21. 21. Preparations Available • Zoladex depot • Decapeptyl depot monthly/3 monthly • Lupride depot & daily • Many other preperations daily dose (blossom/luprofact/lucrin/gonapeptil) • Nasarel (multiple doses) • Buserlin/Zerlin/suprafact sub cut daily dose
  22. 22. MODE OF ACTION • GnRH agonists intially have similar short term effects as GnRH. • They bind to the receptors which undergo dimerization & initiate a cascade of events culminate in synthesis & secretion of FSH & LH • FLARE UP 4 times FSH and 10 times LH release
  23. 23. UP REGULATION • An increase in number of receptors amplifies the synthesis and release of gonadotrophins. • This occurs during pulsatile endogenous GnRH release or its superactive agonists. • Thus upregulation of receptors facilitates ready synthesis and release of large amount of gonadotropins when needed. • FLARE UP EFFECT
  24. 24. • Over the time b/o over abundance of agonists with longer half life, the dimer form of receptors is favoured and the receptors go into the cell and cannot come back so • Cannot respond to subsequent pulses of GnRH • Thus the gonadotrops become desensitised and this is called down regulation of GnRH receptors
  25. 25. DESENSITIZATION • When the GnRH receptors exposed to GnRH agonists for a prolonged period, the cells lose their ability to respond to the stimulus with their original sensitivity. • Process is rapid & reversible. • Process operates at both the receptor level & by post receptor modification WHAT IS DOW N ON Down regulation
  26. 26. • GnRH is released in a pulsatile fashion but a continuous supply of GnRH suppresses gonadotrophin secretion by desensitization of gonadotrophs. • This property is utilised in number of therapeutic options.
  27. 27. • Slowly and steadly FSH and LH conc falls,and so does estradiol and progesterone levels,indicating inhibition of ovarian steroidogenesis and follicular growth. • This property is utilised in number of therapeutic options.
  28. 28. CLINICAL APPLICATIONS • Diagnostic use • Gonadal stimulation • ART • Precocious puberty • Endometriosis • Fibroids • Hormone dependent tumours • Hirsutism • DUB • Endometrial ablation • PMS • Prostatic malignancy • Trigger ovulation
  29. 29. Diagnostic use: GAST TEST Similar to clomiphene challenge test used to evaluate hypo-thalamic pituitary ovarian axis.
  30. 30. Gonadal stimulation • Pulsatile administrationof GnRH in physiologic doses mimics endogenous release & stimulates the ovaries. • Sub –cut 5-20 mcg every 90 mins or IV 20-25mcg every 90mins. Especially for hypothalamic amenorrhoea and PCOD
  31. 31. Precocious Puberty • Suppression of pituitary-gonadal function is the aim • Long term agonists are safe and effective • Can be given for yrs till normal age of puberty reaches. • More striking aspect is regression of secondary sex characters
  32. 32. Endometriosis • Ability to produce amenorrhoea and anovulation is the main basis • Mild to moderate stages medically managed. • Severe managed with surgery &/or in combination with medical. • Depot preparations are widely used.
  33. 33. Though surgical removal is the most effective method But the main goal of pre-operative agonists is; *Reduce blood loss during subsequent surgery *reduce the tumor size, lesser operating time *lesser complications *where surgery not possible WITH 3 MTHS TT 40-60% REDUCTION IN SIZE FIBROIDS
  34. 34. Agonists and ART • Down regulation of HPO axis - prevention of LH surge • Suppression of endogenous FSH / LH, elevated basal LH levels (PCOS) and active endometriosis • Recruitment of a uniform cohort of follicles • Programming of cycles • Avoiding weekends
  35. 35. AGONISTS AND ART • augmentation of follicular activity • achieve higher number of oocytes • higher number of embryoes • increased pregnancy rates
  36. 36. MODE OF DELIVERY ORALLY ANALOGUES ARE RAPIDLY DESTROYED MAYBE GIVEN: • PARENTRALLY • NASAL SPRAY • VAGINAL PESSARIES • DEPOT PREPARATIONS ARE ALSO AVAILABLE • BIOLOGICAL EFFICACY OF NASAL SPRAY IS LOWER THAN SUB CUTANEOUS
  37. 37. Assess Downregulation RULE OF FIVES TO ASSESS DOWN REGULATION LESS THAN 5 FOLLICLES LESS THAN 5 MM SIZE OF FOLLICLES LESS THAN .5 MM ENDOM THICKNESS(actually .3) LESS THAN 50 pgm ESTRADIOL(actually 30) LESS THAN .5 ngm PROGESTERONE TVS
  38. 38. GnRh Agonists 1. Long Protocol 2. Short flare up 3. Ultra short 4. Ultra long
  39. 39. agonist agonist agonist 2 3 4 2 3 4 5 6 7 8 9 10 11 12 21 (luteal) 2 3 4 5 6 7 8 9 10 11 hCG hCG hCG 150 /225 FSH / hMG daily 150 rec FSH / 225 hMG daily Conventional Protocols 150/225 FSH / hMG daily Flare up of a dying corpus luteum Elevated LH levels in the early follicular phase Follicular dominance - one follicle races ahead of the others - no uniform cohort Premature LH surge Better suited for poor responders (advantage of the flare-up effect) Reduced consumption of gonadotropins hence reduced cost of therapy Premature LH surge Increased consumption of gonadotropins result of complete suppression of endogenous FSH and LH Increased cost of treatment Inadvertent administration of GnRHa during early pregnancy Reversibility takes weeks
  40. 40. Disadvantages of agonists • Increased consumption of gonadotropin as a result of complete suppression of endogenous FSH and LH • Increased cost of treatment • Inadvertent administration of GnRHa during early pregnancy
  41. 41. Side effects •Hypo estrogenic state; •Hot flushes •Head aches •Vaginal dryness •Mood instability •Insomnia •Decreased libido •Dizziness •Altered lipid profile •Osteoporosis
  42. 42. estrogen deprivation • GnRH agonists administration in luteal phase ,a stage of hypoestrogenism is induced ,during this period women may suffer from common symptoms of hypoestrogenism; • Hot flashes • Insomnia • Short term memory lapses • Head aches
  43. 43. THERE AROSE A NEED TO LOOK FOR ANOTHER DRUG TO PREVENT LH SURGE
  44. 44. • The introduction of GnRH antagonists in assisted reproductive technologies (ART) at the beginning of this decade was met with mixed reactions. A series of theoretical and evidence-based advantages supported their use Tarlatzis et al., 2006
  45. 45. GnRH Agonist vs GnRH Antagonist: Mechanism of Action Flare-up GnRH receptor desensitization Long GnRH Agonist Protocol Pituitary GnRH Gonadotropin suppression FSH LH GnRH receptor Hypothalamus GnRH agonist GnRH FSH LH GnRH Antagonist Protocol Pituitary GnRH Direct gonadotropin suppression GnRH receptor Hypothalamus GnRH antagonist FSH LH GnRH agonist
  46. 46. Thus the need for antagonists is a real one
  47. 47. ANTAGONISTS • There is no dimer formation • It outcompetes the GnRH for the GnRH receptors and blocks the ability of GnRH to initiate dimer formation • As a result monopolization of GnRH antagonist, there is no secretion of FSH and LH. • As long as sufficient antagonist is present suppression is sustained
  48. 48. GnRH ANTAGONISTS • Competitively bind to pit.GnRH receptors & do not release gonadotrophins. • Possible to modulate hormone suppression by dose . • Do not cause initial flare up. • Within hours secretion of gonadotropins decreases. • Do not cause pituitary exhaustion. • Can respond to adequate stimulus immediately.
  49. 49. • Introduction of GnRH antagonists provides prevention of premature LH surge but with distinct advantages – More timely suppression of LH – No symptoms associated with GnRH agonist flare and downregulation 1. Hughes et al. Fertil Steril. 1992;58:888. 2. Devroey et al. Hum Reprod. 2009;24:764.
  50. 50. ANTAGONISTS • Multiple amino acid substituition permits synthesis of antagonists. • Which bind to GnRH receptors and provide competitive block for naturally synthesised GnRH.
  51. 51. Antagonists • Cetrolix • Iturelix • Azaline B • Ganirelix • Abarelix • Antarelix
  52. 52. Antagonists Results in Rapid Reduction in LH 0 2 4 6 8 6 7 8 9 10 11 12 Days Serum FSH/LH (IU/L) 0 3 6 9 12 Orgalutran (ng/mL) FSH LH Orgalutran -32% -74% Serum concentrations of Orgalutran, FSH, and LH following the final (day 7) Orgalutran 0.25 mg injection Out and Mannaerts. Hum Fertil. 2002;5:G5. Oberye et al. Fertil Steril. 1999;72:1006.
  53. 53. Controlled Ovarian Hyperstimulation Regimens for Assisted Reproductive Technology GnRH Antagonist Protocols GnRH Agonist Protocols 225 IU per day (150 IU Europe) Individualized Dosing of FSH/HMG 250 µg per day antagonist Individualized Dosing of FSH/HMG GnRHa 1.0 mg per day up to 21 days 0.5 mg per day of GnRHa 225 IU per day (150 IU Europe) Day 6 of FSH/HMG Day of hCG Day 1 of FSH/HMG Day 6 of FSH/HMG Day of hCG 7 – 8 days after estimated ovulation Down regulation Day 2 or 3 of menses Day 1 FSH/HMG OCP
  54. 54. KEY DIFFERENCES BETWEEN ANTAGONISTS AND AGONIST • No initial flare effect • No estrogen deprivation symptoms • Shorter tt protocol • Reduced gonadotropin use • Flexibility • Rapid reversibility • Recovery phase is much shorter(2-4 days) • Patients more inclined to drop out of agonist regime.
  55. 55. NO INITIAL FLARE UP • Initial response of agonists is stimulatory. • For achieving a clinically suppressed state –14-21 days. • Antagonists in contrast have immediate action.
  56. 56. • GnRH antagonists are not started until stimulation is well under way and estradiol levels are high • So no estrogen deprivation symptoms
  57. 57. SHORTER TREATMENT • Duration of antagonists cycle is much shorter • Difference is 4 days vs 22 days (north american study group trial) • Albano et al. difference is 6 days vs 27 days
  58. 58. REDUCED GONADOTROPIN USE • North American ganirelix study group trial showed that duration of recombinant FSH was slightly shorter (8 days)as compared to leuporide group(10 days) • Total dose was also lower( 1800 i.u vs 2025 i.u)
  59. 59. Antagonist what more… • Holds promise for the PCOS • Reduction in the incidence of OHSS • Agonist can be used as a trigger instead of hCG to drastically reduce risk of OHSS – More physiological – Lower half life (60 mins vs 32 – 34 hrs) – Lower incidence of OHSS
  60. 60. FLEXIBILITY • ANTAGONISTS SHOW RAPID SUPPRESSION OF ENDOGENOUS LH/FSH DURING ALL PHASES OF MENSTRUAL CYCLE
  61. 61. Fixed Start Day Protocol Day 6 of stimulation 1 2 7 10 12 0.25 mg Cetrorelix HCG OPU/IUI Rec FSH
  62. 62. Flexible Start Day Protocol 1 7 10 0.25 mg Cetrorelix HCG OPU/IUI 1 6 7 8 9 1011 13 USG > 14 mm E2 > 200-300 pg/ml Rec FSH/hMG
  63. 63. Timing of antagonist addition • Controversial • Introduction too soon counterproductive and leads to shut off potential endogenous FSH, interfering with early follicular recruitment. • Too late will not prevent premature LH surge
  64. 64. RAPID REVERSIBILITY • Because GnRH receptors remain functional although blocked ,if sufficient GnRH or GnRH agonists are given to out compete the antagonists, secretion of FSH and LH results
  65. 65. GnRH antagonists in normal responders • Start FSH or HMG on d-2 and as soon the follicle reaches 12-14 mm add antagonist till hCG day.
  66. 66. POTENTIAL OTHER USES • Suppressing LH surge in cases where pt forgets to take agonists by chance. • Triggering ovulation in antagonist cycle by agonist in hyperstimulated cases • Synchronising ovum recepient cycles
  67. 67. Major points to consider in normal responders • Expect a high estradiol level on D-6 • Do not cutback on dose of recombinant FSH • OC pretreatment can be included for cycle timing,but donot expect better response • Use flexible start of antagonist ,not preferably after D-8
  68. 68. IN POOR RESPONDERS • Who is a poor responder ? • Acc. To reproductive medicine associates of NY • Exhibits 1 or 2 follicle response • Peak estradiol levels not >500 pg at hCG administration • Requiring excessive amount or duration of gonadotropins(>450 I.u)
  69. 69. Soft Ovarian Stimulation:Poor responders Craft et al – CC/Gn with antagonist in poor responders & PCOS USG E2 USG E2 USG E2 HCG 5000 10,000 ET D2 ET D3 ET D5 Blastocyst OPU IUI 35-37 hr 1 2 3 4 5 6 7 8 9 101112 Progesterone IM Oral Vaginal CC GnRH antagonist FSH/HMG
  70. 70. Advantages of antagonist cycles • Same success rate as agonists • Lower cancellation rate • Reduction in duration of GnRH agonists • Lower risk of OHSS • Avoidance of estrogen deprivation symptoms • Lower dropout rates.
  71. 71. Issues to be settled
  72. 72. Q.1 • In a fixed dose regime of antagonist,is there a need to increase the dose of FSH or LH supplementation while starting the antagonist on D-5 ?
  73. 73. Best Practices for GnRH Antagonist Protocols: Evidence Does Not Support Supplementation of LH Activity 29.5 31.7 0 5 10 15 20 25 30 35 40 35 32.1 0 5 10 15 20 25 30 35 40 Bosch et al1 Meta-analysis2 recFSH recFSHrecFSH + rLH hMG Ongoingpregnancyrate (%) P=0.6 1 P=NS 1. Bosch et al. Hum Reprod. 2008;23:2346. 2. Baruffi et al. Reprod Biomed Online. 2007;14:14. Ongoingpregnancyrate (%)
  74. 74. Q. 2 Fixed or flexible protocol?
  75. 75. Ganorelix / cetrorelix day 9 OR Gano / cetro day 6 - 12 2 3 4 5 6 7 8 9 10 11 12 Single shot
  76. 76. Q.3 • PCOS with delayed cycles ,when to start antagonists ?
  77. 77. Q.4 • What is the time gap between the last antagonist injection and hCG?
  78. 78. •Prevent premature LH surge •Protect oocyte from deleterious effect of high LH •Compared to agonist :- • shorter cycle of treatment, • more conception, •fewer miscarriages, • reduced amount of gonadotropins needed • monofollicular growth, • reduced risk of OHSS & multiple pregnancy GnRH antagonist in IUI cycles
  79. 79. The ideal Indian protocol 100 mg CC /L day 225 hMG / 225 IU rec FSH 0.25 mg antagonist/day 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 7500units hCG
  80. 80. “Think it over...” Understanding of the pituitary down regulation enables you to take maximum advantage of the interplay exo and endogenous hormonal milieu of the body. BUT In future antagonists might play a major role in ART cycles.
  81. 81. Antagonists Phase 3 Trials: Duration of FSH Stimulation 9 8 9 10 10 11 0 2 4 6 8 10 12 EU trial NA trial EU/ME trial DaysofFSH stimulation Triptorelin Buserelin Leuprolide Orgalutran Out and Mannaerts. Hum Fertil. 2002;5:G5.
  82. 82. Antagonists Phase 3 Trials: Amount of recFSH Required 1,500 1,800 1,350 1,800 2,025 1,800 0 500 1,000 1,500 2,000 2,500 Triptorelin Buserelin Leuprolide IUofFSHrequired EU trial NA trial EU/ME trial Orgalutran Out and Mannaerts. Hum Fertil. 2002;5:G5.
  83. 83. Increased consumption and days of stimulation
  84. 84. Antagonists Phase 3 Trials: Number of Oocytes and Good Quality Embryos EU trial NA trial EU/ME trial Triptorelin Buserelin Leuprolide 8.7 11.7 7.9 9.7 14.1 9.6 0 2 4 6 8 10 12 14 16 3.3 4.3 2.7 3.5 4.8 2.9 0 1 2 3 4 5 6 7 8 9 10 EU trial NA trial EU/ME trial EU = European; NA = North American; ME = Middle East. Out and Mannaerts. Hum Fertil. 2002;5:G5. Orgalutran Number Number Good Quality Embyros Oocytes
  85. 85. Antagonists Phase 3 Trials: Ongoing Pregnancy Rate per Started Cycle 20.3 30.8 31 25.7 36.4 33.9 0 5 10 15 20 25 30 35 40 Orgalutran Triptorelin Buserelin Leuprolide EU trial NA trial EU/ME trial Ongoingpregnancyrate(%) Out and Mannaerts. Hum Fertil. 2002;5:G5.
  86. 86. Pregnancy outcome slightly better with agonist
  87. 87. MORE EXPENSIVE MORE EFFECTIVE
  88. 88. • It is not uncommon to see that pts who are normally ovulating when kept on long luteal protocol,then given stimulation, fail to stimulate and become refractory. • These pts have been oversuppressed
  89. 89. Antagonist vs long protocol poor responders
  90. 90. Modifying protocols for poor responders • Minidose agonist protocol • Microdose flareup protocol • Antagonist protocol
  91. 91. GnRH Antagonists vs Agonists poor responders or PCOS • Two studies on poor responders comparing the protocols demonstrated that both had similar pregnancy rates • Four RCTs related to PCOS also demonstrated similar results. Greisinger G et al 2006
  92. 92. GnRH Antagonist Strategy Is Associated With a Lower Dropout Rate vs Long GnRH Agonist Strategy SET = single embryo transfer; DET = double embryo transfer. Adapted from Verberg et al. Hum Reprod. 2008;23:2050. Likelihoodofcontinuingtherapy(%) Cycle number 95.9% 93.7% 78.6% 88.3% 75.9% P=0.034 GnRH antagonist plus SET GnRH agonist plus DET Continuation of therapy following each cycle 50 60 70 80 90 100 0 1 2 3
  93. 93. GnRH Antagonists For Treatment Of PCOS Why should the antagonists be used rather than the agonists? Three reasons • Significantly less gonadotropin is required • Better compliance due to the number of injections are approximately 4 to 5 with the GnRH antagonist compared with anywhere between 21 to 25 with the GnRH agonist. • Reduced risk of developing OHSS. • GnRH agonist can be used to trigger ovulation Fertility and Sterility Vol.80, Suppl.1, Jul 2003
  94. 94. Ongoing pregnancy rate per couple with one cycle of FSH/IUI with and without GnRH antagonist treatment. Hum. Reprod. Update 2009;15:265-277 © The Author 2009. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For Permissions, please email: journals.permissions@oxfordjournals.org
  95. 95. GnRH Antagonists Are Associated With More Favorable Outcomes vs GnRH Agonists Among Women at High Risk for OHSS 56.3 43.7 76.3 27.6 32.2 67.8 96.6 11.5 0 10 20 30 40 50 60 70 80 90 100 Canceled cycles Oocyte retrievals Embryo transfer OHSS GnRH agonist GnRH antagonist P<0.001 P<0.001 P=0.003 P=0.006 Percent Ragni et al. Hum Reprod. 2005;20:2421. Investigator-driven, prospective observational study of women (N=87) at high risk for OHSS, who were treated with a GnRH antagonist protocol following a previous cycle with a GnRH agonist protocol
  96. 96. OHSS
  97. 97. Antagonists vs Long GnRH Agonist: Effects on the Endometrium • No relevant alteration in endometrial thickness or pattern was observed with standard or high dose of Orgalutran • Endometrial dating, estrogen and progesterone receptor expression, and endometrial surface structure were unaffected with Orgalutran treatment • Buserelin was associated with indications of an arrest in endometrial development • Expression of “window of implantation” genes with Orgalutran treatment more closely paralleled the pattern observed during a natural cycle compared with buserelin Simon et al. Hum Reprod. 2005;20:3318.
  98. 98. Antagonists vs Long GnRH Agonist: Effect on Expression of Implantation Genes Number of Genes With Differential Regulation Between the Natural Cycle (Day LH +7) and the Treatment Regimens (Day HCG +7) and Within the Window of Implantation* Regimen No. of Genes With Expression Increased; Decreased† Window of Implantation Genes All Genes Typically Up- regulated‡ (n=894) Typically Down- regulated‡ (n=504) Orgalutran 0.25 mg/d ↑ 22; ↓ 69 ↑ 0; ↓ 46 ↑4; ↓ 0 Orgalutran 2 mg/d ↑ 88; ↓ 24 ↑ 0; ↓ 15 ↑7; ↓ 1 Buserelin long protocol ↑ 22; ↓ 100 ↑ 3; ↓ 76 ↑4; ↓ 2 *Differential regulation was defined as a ≥100% increase or ≥50% decrease in expression. †Compared with values on day LH +7 of natural cycle. ‡Genes whose expression is typically upregulated or typically downregulated during the window of implantation (day 2–7 after the LH surge), according to Horcajadas et al 2005. Adapted from Simon et al. Hum Reprod. 2005;20:3318; Horcajadas et al. Mol Hum Reprod. 2005;11:195. Expression of “window of implantation” genes more closely paralleled the pattern observed during a natural cycle with Orgalutran than with buserelin
  99. 99. Pooled Antagonists Clinical Studies: Development of Pregnancies and Birth Outcomes No. (%) Orgalutran GnRH Agonist Ongoing pregnancies (≥16 wk) 340 134 Singleton 258 (75.9) 91 (67.9) Multiple 82 (24.1) 43 (32.1) Total fetuses (≥16 wk) 432 184 Total liveborn infants 419 (97.0) 179 (97.3) Fetal deaths None None Boerrigter et al. Hum Reprod. 2002;17:2027. Data on birth outcomes pooled from 5 clinical studies in women with ongoing pregnancy (N=474)
  100. 100. Pooled Antagonists Clinical Studies: Neonatal Outcomes Orgalutran GnRH Agonist n=419 n=179 Mean gestational age, weeks 38.0 37.4 Term birth, no. (%) 306 (73.0) 107 (59.8) Preterm birth, no. (%) (≥33 weeks and <37 weeks) 87 (20.8) 47 (26.3) Very preterm birth, no. (%) (<33 weeks) 27 (6.2) 25 (14.0) Mean birth weight, g 2,834 2,716 n=424 n=181 Congenital malformations (%) 7.5 5.5 Major malformations (%) 4.5 3.3 Data on neonatal outcomes pooled from 5 clinical studies in women with ongoing pregnancy Boerrigter et al. Hum Reprod. 2002;17:2027.
  101. 101. Antagonists Favorable Safety Profile No. of Patients Orgalutran (n=1,217) Buserelin (n=236) Leuprolide (n=99) Triptorelin (n=111) Subjects with AEs 280 (23.0) 74 (31.4) 41 (41.4) 24 (21.6) Subjects with SAEs 37 (3.0) 11 (4.7) 0 (0) 3 (2.7) Subjects with drug-related AEs (including SAEs)* 36 (3.0) 9 (3.8) 6 (6.1) 2 (1.8) *Judged by the investigator as definitely, probably, or possibly related to study drug. Borm and Mannaerts. Hum Reprod. 2000;15:1490. Fluker et al. Fertil Steril. 2001;75:38. European and Middle East Orgalutran Study Group. Hum Reprod. 2001;16:644. AEs With Orgalutran vs GnRH Agonists: Pooled Data From Dose-Finding and Phase 3 Trials No significant differences were seen in AEs between the 2 groups
  102. 102.  No OCP pretreatment  Check patient cycle day 2  FSH 100-225 IU  Antagonist earlier than later  LH not necessary Suggested GnRH Antagonist Protocol Cycle day 2 Transvaginal US + (if desired) hormonal profile This suggested protocol represents a “best estimate” given current data and clinical experience. Further data are required before more concrete recommendations can be made. For regular IVF patients:  5-9 antral follicles per ovary  Age <35 years  No PCOS  No history of poor responses  No endometriosis Duration of treatment based on clinical judgment in consultation with patient (usually 2 USs) Cycle day 2/3 Start FSH 150-200 IU. Continue Stimulation days 5-6 Start GnRH antagonist administered daily. Continue Monitoring according to clinic practice  US (+ blood test if required)  FSH dose adjustments may be considered 3 follicles 15-19 mm Day of triggering  Ensure interval between antagonist and hCG does not exceed 30 h  hCG 5000-10,000 IU Oocyte retrieval 36 h YES NO US = ultrasonogram; OCP = oral contraceptive pill. Devroey et al. Hum Reprod. 2009;24:764.
  103. 103. Antagonist as a Key Component of Patient-Centered Therapy • Good pregnancy rates • Reduced risk of OHSS • Reduction of stress associated with physical and psychological treatment burden – No side effects related to flare-up or downregulation – Fewer injections – Shorter treatment cycles – Shorter duration of stimulation Devroey et al. Hum Reprod. 2009;24:764.
  104. 104. ONE SIZE FITS ALL ?
  105. 105. Meta-analyses of GnRH Antagonists vs GnRH Agonists: Pregnancy Outcomes • The 2 studies had different results for pregnancy outcomes *Live birth rate included ongoing pregnancies (Al-Inany) or calculated rates (Kolibianakis). OR = odds ratio. 1. Al-Inany et al. Cochrane Database Syst Rev. 2006;3:CD001750. 2. Kolibianakis et al. Hum Reprod Update. 2006;12:651. Al-Inany1 Kolibianakis2 OR 0.82 0.86 95% CI 0.69-0.98 0.72-1.02 P value 0.03 0.085 Live Birth Rate* in Meta-analyses, GnRH Antagonists vs GnRH Agonists
  106. 106. Meta-analyses Confirm That GnRH Antagonists Have a Better Safety Profile vs GnRH Agonists Al-Inany1 Kolibianakis2 Duration of analog treatment −20.90 days (95% CI −22.20, −19.60) −19.48 days (95% CI −21.05, −17.91) Duration of ovarian stimulation −1.54 days (95% CI −2.42, −0.66; P=0.0006) −1.13 days (95% CI −1.83, −0.44) Risk of severe OHSS OR 0.61 (95% CI –0.42, 0.89; P=0.01) RR 0.46* (95% CI 0.26, 0.82; P=0.01) Interventions to prevent OHSS OR 0.44 (95% CI 0.21, 0.93; P=0.03) *For every 59 women treated with a GnRH agonist vs GnRH antagonist, 1 additional case of severe OHSS will occur. RR = risk ratio. 1. Al-Inany et al. Cochrane Database Syst Rev. 2006;3:CD001750. 2. Kolibianakis et al. Hum Reprod Update. 2006;12:651.
  107. 107. GnRH Antagonists vs GnRH Agonists: Patients With Poor Response or PCOS PCOS = polycystic ovary syndrome. Griesinger et al. Reprod Biomed Online. 2006;13:628. Poor Responders PCOS Clinical Pregnancy Rates
  108. 108. GnRH Antagonist and Long GnRH Agonist Strategies Result in Comparable Cumulative Pregnancy Rates 0 20 40 60 0 3 6 9 12 Adapted from Heijnen et al. Lancet. 2007;369:743. GnRH agonist with DET GnRH antagonist with SET %ofpregnancies leadingtotermlive birth Months since randomization Singleton term live birth Proportion of pregnancies leading to cumulative term live birth within 12 months after starting IVF
  109. 109. GnRH Antagonist and GnRH Agonist Strategies Result in Shorter Treatment, Better Safety, and Lower Cost Heijnen et al. Lancet. 2007;369:743. GnRH Antagonist (n=444) GnRH Agonist (n=325) P Value Days of injections 8.5 25.3 <0.0001 Days of stimulation 8.3 11.5 <0.0001 Total dose of FSH (IU) 1,307 1,832 <0.0001 Incidence of OHSS (%) 1.4 3.7 0.04 Mean total costs €8,333 €10,745 0.006
  110. 110. Thanks
  111. 111. CLOMIPHENE CITRATE
  112. 112. EVALUATION
  113. 113. GONADOTROPHINS ROLE • FSH IS THE KEY GONADOTROPHIN • Plays crucial role in • Recruitment • Selection • Dominance during follicular phase • Also stimulates granulosa cells LH receptor expression • Concept of FSH window
  114. 114. GnRH • Plays a key role in functioning of hypothalamic-pituitary axis . • Is a decapeptide • Regulates trophic function of anterior pituitary gland. • Regulates production & release of both LH & FSH in the gonadotrophs of ant. Pituitary.
  115. 115. GnRH • is produced & secreted by a group of neurons located in the arcuate nucleus of medial basal hypothalamus & preoptic area of ventral hypothalamus. • These molecules are transported to pituitary by intricate network of capillaries.
  116. 116. • GnRH then binds to specific receptors in the plasma membrane of the anterior pituitary gonadotrops • Where it causes synthesis ,storage and release of luteinizing hormone and follicle stimulating hormone.
  117. 117. PHYSIOLOGY OF GnRH ACTION • Gonadotrophs of ant.pituitary release FSH and LH rhythmically in response to rhythmic release of GnRH. • Pulsatile frequency varies from 71 mins in late follicular phase to 216 mins in luteal phase . • This secretion of GnRH is governed by GnRH pulse generators which resides in mediobasal hypothalamus.
  118. 118. • Puberty starts when GnRH pulse generator is released from suppressive effects of gonadostats at around 8.5 – 12.5 yrs in girls and 9.5-13.5 yrs in boys. •This pulse generator is operative during fetal life and in early infancy but is suppressed by intrinsic inhibitory control
  119. 119. • However under certain circumstances estradiol can have positive influence,on GnRH secretion like prior to ovulation. • GnRH secretions are negatively modulated by gonadal steroids. • Prolonged strenuous exercise and severe weight loss can inhibit GnRH secretion.
  120. 120. The number of receptors in the membrane of gonadotrophs change with altered physiological conditions and are subjected to up & down regulation.
  121. 121. UP REGULATION • An increase in number of receptors amplifies the synthesis and release of gonadotrophins. • This occurs during pulsatile endogenous GnRH release or its superactive agonists. • Thus upregulation of receptors facilitates ready synthesis and release of large amount of gonadotropins when needed.
  122. 122. GnRH AGONISTS SYNTHETIC AGONISTS • INCREASE STABILITY AND BINDING AFFINITY TO ITS RECEPTORS. • 100-200 TIMES HIGHER. •GnRH has short half life of a few minutes & rapidly degraded by endopeptidases.
  123. 123. •It is possible to readily synthesise GnRH agonists by using solid peptide synthesis. It is possible to introduce amino acid substitution to prolong the half life . Position 6 of amino acid sequence is important for inactivation. 2 and 3 for gonadotropin release 1,6 and 10 for binding • 1 2 3 4 5 6 7 8 9 10 GnRH shows two phases with half lives of 2-8 mins for fast and 15-60 mins for slower phase
  124. 124. GnRH agonists • First synthesised in 1972 • produced by altering the amino acids at position 6 and /or 10,resulted in compounds with higher affinity for the GnRH receptors and a long half- life due to their resistance to cleavage by endopeptidases & reduced susceptibility to enzymatic degradation • Half life is of few hrs.
  125. 125. Agonists and ART • Down regulation of HPO axis - prevention of LH surge • Suppression of endogenous FSH / LH, elevated basal LH levels (PCOS) and active endometriosis • Recruitment of a uniform cohort of follicles • Programming of cycles • Avoiding weekends
  126. 126. GnRh Agonists 1. Long Protocol 2. Short flare up 3. Ultra short 4. Ultra long (long follicular) (long luteal) (ultra long)
  127. 127. 2 3 4 2 3 4 5 6 7 8 9 10 11 12 21 (luteal) 2 3 4 5 6 7 8 9 10 11 hCG hCG hCG 150/225 FSH / hMG daily 150 /225 FSH / hMG daily 150 rec FSH / 225 hMG daily
  128. 128. • No difference between GnRH agonist or antagonist in terms of cycle cancellation rate, number of mature oocytes, or pregnancy rate. • In analysis of GnRH agonist microdose flare vs antagonist (4 trials) - significantly higher rate of oocytes retreived in GnRH-a flare cycles • no difference in pregnancy outcomes • More trials needed Franco, JG Jr et al, Reproductive Biomedicine Online, 2006
  129. 129. Stress Impacts IVF Success • Several indicators of stress are significantly higher in women undergoing stimulated IVF compared with unstimulated IVF or undergoing gynecologic surgery not related to infertility1 – Prolactin, cortisol, and state anxiety score all increased during stimulated IVF treatment1 • Anxiety associated with IVF treatments may lead to inadvertent noncompliance with recommended gonadotropin dosing, a poor or excessive ovarian response, and possibly a poor cycle outcome2 1. Harlow et al. Hum Reprod. 1996;11:274. 2. Noorhasan et al. Fertil Steril. 2008;90:2013.e1.
  130. 130. Stress Impacts IVF Success (cont’d) • COS with less complicated treatment regimens and fewer injections results in significantly fewer (3% vs 23% with more complicated regimens, P<0.001) patients reporting that the stress associated with treatment was considered “unacceptable”1 • The psychological burden of IVF treatments was the primary reason cited among couples who discontinued treatment before 2,3 1. Højgaard et al. Hum Reprod. 2001;16:1391; 2. Olivius et al. Fertil Steril. 2004;81:258; 3. Verberg et al. Hum Reprod. 2008;23:2050; 4. Smeenk et al. Hum Reprod. 2001;16:1420.
  131. 131. 4 4 5 5 6 7 16 18 0 5 10 15 20 Physical or Psychological Treatment Burden as a Primary Reason for Dropout Physical or psychological burden of treatment Unknown Relational problems/divorce Others Adoption Poor embryo quality Poor response/signs of ovarian aging Ethical objections to ICSI treatment after failed IVF treatment Among 384 couples undergoing IVF treatment, 65 (17%) drop Adapted from Verberg et al. Hum Reprod. 2008;23:2050. Causes for Dropout No. of patients
  132. 132. KEY • Optimizing GnRH antagonists is clear understanding of pharmacological differences in agonists and antagonists • More convenient • Fewer injections • Fewer side effects • Easier to implement ,schedule and manage.
  133. 133. Structure of Orgalutran NH2 NAcD2Nal D4CIPhe D3Pal DhArg(Et2) hArg(Et2) D-Ala Orgalutran NH2 pGlu His Trp Ser Tyr Gly Leu Arg Pro Gly Endogenous GnRH Ser Tyr ProLeu
  134. 134. 0 5 10 15 20 %ofpatientswithLH≥10IU/L Daily dose of Orgalutran (mg) The ganirelix dose-study finding group. Hum Reprod. 1998;13:3023. Orgalutran Dose-Finding Study: Suppression of LH Surges Dose selected for phase 3 studies 0.0625 (n=31) 0.125 (n=65) 0.25 (n=69) 0.5 (n=69) 1 (n=65) 2 (n=30)
  135. 135. Orgalutran Phase 3 Trials: Study Design Inclusion Criteria - Healthy women undergoing COS for IVF or ICSI - Women aged 18 to 39 years - Regular cycles between 24 and 35 days - BMI 18 to 29 kg/m2 Orgalutran Puregon Puregon GnRH agonist Downregulation Cycle day 21-24 Day 2 or 3 of menses hCG* Day 6 of rFSH *≥3 follicles ≥17 mm. Adapted from Out and Mannaerts. Hum Fertil. 2002;5:G5. Borm and Mannaerts. Hum Reprod. 2000;15:1490. Fluker et al. Fertil Steril. 2001;75:38. European and Middle East Orgalutran Study Group. Hum Reprod. 2001;16:644. Luteal phase support Luteal phase support
  136. 136. COH • 3 choices • FSH with antagonist • Clomiphene with FSH/with antagonist • Long luteal protocol
  137. 137. Advantages of GnRH Antagonists vs GnRH Agonist Long Protocol • No initial flare-up • No estrogen deprivation symptoms • Shorter treatment • Reduced gonadotropin use • Flexibility • Administration only during period needed to suppress endogenous LH surge • Lower risk of OHSS • Rapid reversibility of pharmacodynamic action
  138. 138. Meta-analyses of GnRH Antagonists vs GnRH Agonists • Two recent meta-analyses evaluated randomized, controlled trials of GnRH antagonists vs GnRH agonists in IVF1,2 • These meta-analyses included different studies, used different measures of efficacy, and reached different conclusions regarding relative efficacy – The Al-Inany study included non peer-reviewed data and included studies on IUI IUI = intrauterine insemination. 1. Al-Inany et al. Cochrane Database Syst Rev. 2006;3:CD001750. 2. Kolibianakis et al. Hum Reprod Update. 2006;12:651.

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