{"entity":{"id":"intermittent-androgen-deprivation","kind":"term","name":"Intermittent androgen deprivation (IAD)","aka":["IAD","IADT","intermittent hormone therapy","intermittent androgen suppression","treatment holiday","hormone therapy break"],"tldr":"Taking planned breaks from hormone therapy once the PSA has settled, restarting when it rises again. The aim is to give a man time back with his energy, his libido and his mood. The largest trial found the benefit was real but lasted about three months, and could not rule out a worse chance of survival.","summary":"Intermittent androgen deprivation is a strategy of stopping androgen deprivation after an induction period in men who have responded, allowing testosterone to recover, and restarting on a defined trigger. NICE NG131 recommendation 1.4.1 says to consider intermittent therapy for people having long-term androgen deprivation, other than in the adjuvant setting, and to discuss the rationale, the limited evidence for a reduction in side effects, and the effect on progression. Recommendation 1.4.2 sets the practical rule: measure prostate-specific antigen every 3 months, and restart androgen deprivation if the level reaches 10 nanograms per millilitre or above, or if there is symptomatic progression.\n\nThe evidence is SWOG 9346, and it is honestly inconclusive. Hussain and the Southwest Oncology Group enrolled 3,040 men with newly diagnosed metastatic hormone-sensitive prostate cancer, gave seven months of androgen deprivation, and randomised the 1,535 whose prostate-specific antigen fell to 4 nanograms per millilitre or below to continuous or intermittent therapy, with co-primary objectives of non-inferior survival, bounded by a hazard ratio of 1.20, and quality of life at three months. Median survival was 5.8 years continuous against 5.1 years intermittent, hazard ratio 1.10 with a 90 percent confidence interval of 0.99 to 1.23. That interval crosses the non-inferiority boundary, so a 20 percent greater risk of death could not be excluded, and too few events occurred to demonstrate inferiority either. Erectile function (p less than 0.001) and mental health (p equals 0.003) were better on intermittent therapy at month 3 and not afterwards. Median follow-up was 9.8 years.\n\nThat is why it is offered as a choice rather than recommended, and why the honest statement to a man weighing it is that the quality-of-life gain is real, measurable and brief, and the survival question is open rather than settled. Two further limits belong with the figures: only men whose prostate-specific antigen fell below 4 nanograms per millilitre after seven months were randomised, so the result does not apply to men who do not achieve that response; and standard of care has changed completely since enrolment, because androgen deprivation alone is no longer first-line treatment for metastatic disease, so the question would have to be re-asked on top of a modern backbone of an androgen receptor pathway inhibitor with or without docetaxel.","asOf":"2026-09-25","links":[{"label":"NICE NG131: prostate cancer, diagnosis and management (recommendations)","url":"https://www.nice.org.uk/guidance/ng131/chapter/Recommendations"},{"label":"Hussain et al., New England Journal of Medicine 2013 (SWOG 9346): intermittent versus continuous androgen deprivation in metastatic prostate cancer","url":"https://doi.org/10.1056/nejmoa1212299"}],"tags":["gu","prostate-glossary"],"related":["paper-hussain-swog-9346-intermittent-androgen-deprivation-nejm-2013","androgen-deprivation-therapy","bipolar-androgen-therapy","idea-prostate-other-cause-mortality-as-a-reported-service-outcome","idea-bio1-alternating-schedules"],"cancers":["prostate","prostate-mhspc","prostate-bcr","prostate-high-risk"],"sections":["hormonal","supportive-care"],"technologies":[],"targets":["androgen-receptor"],"drugs":["leuprolide","bicalutamide"],"companies":[],"institutions":[],"pathways":[],"terms":["adt","androgen-deprivation-therapy","psa","quality-of-life","hazard-ratio","bipolar-androgen-therapy","hot-flushes-on-hormone-therapy","treatment-induced-bone-loss"],"trials":[],"people":[],"bottlenecks":["b-toxicity-qol","b-trial-design","b-survivorship","b-aging-comorbidity"],"keyPapers":["paper-hussain-swog-9346-intermittent-androgen-deprivation-nejm-2013","paper-langley-lancet"],"journals":[],"dependsOn":[],"notes":["What NICE actually asks for, in numbers. Consider it for long-term androgen deprivation outside the adjuvant setting, and discuss three things honestly: the rationale, the limited evidence that side effects improve, and the effect on progression (NG131 1.4.1). If it is used, check the prostate-specific antigen every 3 months and restart at 10 nanograms per millilitre or above, or on symptomatic progression (NG131 1.4.2).","The break is not immediate and it is not complete. Testosterone recovery after stopping a luteinising hormone-releasing hormone agonist takes months and is slower the longer the treatment has run and the older the man; some men never recover normal levels. A man expecting to feel like himself within weeks of the last injection should be told what the recovery curve actually looks like.","SWOG 9346 is a good trial to read if you want to see what an inconclusive result looks like when it is reported honestly. The authors state plainly that neither non-inferiority nor inferiority was established. A summary that reports it as intermittent therapy is as good as continuous is misreading it."],"category":"Treatment jargon"},"route":"/terms/intermittent-androgen-deprivation/","neighbours":{"paper":[{"id":"paper-hussain-swog-9346-intermittent-androgen-deprivation-nejm-2013","kind":"paper","name":"SWOG 9346: intermittent versus continuous androgen deprivation in metastatic prostate cancer","route":"/key-papers/paper-hussain-swog-9346-intermittent-androgen-deprivation-nejm-2013/"},{"id":"paper-langley-lancet","kind":"paper","name":"Transdermal oestradiol for androgen suppression in prostate cancer: long-term cardiovascular outcomes from the randomised Prostate Adenocarcinoma Transcutaneous Hormone (PATCH) trial programme","route":"/key-papers/paper-langley-lancet/"}],"term":[{"id":"androgen-deprivation-therapy","kind":"term","name":"Androgen deprivation therapy (ADT)","route":"/terms/androgen-deprivation-therapy/"},{"id":"adt","kind":"term","name":"Androgen deprivation therapy (ADT)","route":"/terms/adt/"},{"id":"bipolar-androgen-therapy","kind":"term","name":"Bipolar androgen therapy (BAT)","route":"/terms/bipolar-androgen-therapy/"},{"id":"hazard-ratio","kind":"term","name":"Hazard ratio (HR)","route":"/terms/hazard-ratio/"},{"id":"hot-flushes-on-hormone-therapy","kind":"term","name":"Hot flushes on hormone therapy","route":"/terms/hot-flushes-on-hormone-therapy/"},{"id":"psa","kind":"term","name":"PSA (prostate-specific antigen)","route":"/terms/psa/"},{"id":"quality-of-life","kind":"term","name":"Quality of life","route":"/terms/quality-of-life/"},{"id":"treatment-induced-bone-loss","kind":"term","name":"Treatment-induced bone loss","route":"/terms/treatment-induced-bone-loss/"}],"idea":[{"id":"idea-prostate-other-cause-mortality-as-a-reported-service-outcome","kind":"idea","name":"Report death from other causes as an outcome of the prostate cancer service, split by deprivation and ethnicity","route":"/ideas/idea-prostate-other-cause-mortality-as-a-reported-service-outcome/"},{"id":"idea-bio1-alternating-schedules","kind":"idea","name":"Rotate between drugs on a fixed schedule instead of waiting for failure","route":"/ideas/idea-bio1-alternating-schedules/"},{"id":"idea-prostate-bipolar-androgen-therapy-phase-3-on-pfs2","kind":"idea","name":"Take high-dose testosterone to phase 3, with progression-free survival through the second line as the primary endpoint","route":"/ideas/idea-prostate-bipolar-androgen-therapy-phase-3-on-pfs2/"}],"cancer":[{"id":"prostate-bcr","kind":"cancer","name":"Biochemical recurrence of prostate cancer","route":"/cancers/prostate-bcr/"},{"id":"prostate-high-risk","kind":"cancer","name":"Localised prostate cancer, high and very high risk","route":"/cancers/prostate-high-risk/"},{"id":"prostate-mhspc","kind":"cancer","name":"Metastatic hormone-sensitive prostate cancer","route":"/cancers/prostate-mhspc/"},{"id":"prostate","kind":"cancer","name":"Prostate cancer","route":"/cancers/prostate/"}],"section":[{"id":"hormonal","kind":"section","name":"Hormonal Therapy","route":"/fronts/hormonal/"},{"id":"supportive-care","kind":"section","name":"Supportive Care & Survivorship","route":"/fronts/supportive-care/"}],"target":[{"id":"androgen-receptor","kind":"target","name":"Androgen receptor","route":"/targets/androgen-receptor/"}],"drug":[{"id":"bicalutamide","kind":"drug","name":"Bicalutamide","route":"/drugs/bicalutamide/"},{"id":"leuprolide","kind":"drug","name":"Leuprolide (leuprorelin) and GnRH agonists","route":"/drugs/leuprolide/"}],"bottleneck":[{"id":"b-aging-comorbidity","kind":"bottleneck","name":"Older and multimorbid patients are excluded and undertreated","route":"/bottlenecks/b-aging-comorbidity/"},{"id":"b-survivorship","kind":"bottleneck","name":"Survivorship and late effects are neglected","route":"/bottlenecks/b-survivorship/"},{"id":"b-toxicity-qol","kind":"bottleneck","name":"Toxicity and quality of life are undervalued","route":"/bottlenecks/b-toxicity-qol/"},{"id":"b-trial-design","kind":"bottleneck","name":"Trial design, endpoints and cost","route":"/bottlenecks/b-trial-design/"}]}}