{"id":7253,"date":"2025-06-08T08:37:00","date_gmt":"2025-06-08T03:07:00","guid":{"rendered":"https:\/\/chiralpedia.com\/blog\/?p=7253"},"modified":"2026-06-02T13:16:49","modified_gmt":"2026-06-02T07:46:49","slug":"episode-7-clinical-questions-are-single-enantiomers-always-better","status":"publish","type":"post","link":"https:\/\/chiralpedia.com\/blog\/episode-7-clinical-questions-are-single-enantiomers-always-better\/","title":{"rendered":"Episode 7: Clinical Questions: Are Single Enantiomers Always Better?"},"content":{"rendered":"\n<p class=\"has-vivid-red-color has-text-color has-link-color wp-elements-1 wp-block-paragraph\"><em><strong>&#8220;Science, ethics, and clinical outcomes converge at a difficult question -does the purer mirror image truly heal better?&#8221;<\/strong><\/em><\/p>\n\n\n\n<p class=\"has-ast-global-color-0-color has-text-color has-link-color has-medium-font-size wp-elements-2 wp-block-paragraph\"><strong>Introduction<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The development of single-enantiomer drugs has been heralded as a leap forward in pharmacotherapy, promising greater efficacy, reduced side effects, and more predictable pharmacokinetics. But as the pharmaceutical industry increasingly embraced chiral switches and single-enantiomer innovations, an important clinical question arose: <strong>Are single enantiomers always better than their racemic predecessors?<\/strong> In this episode, we critically examine the clinical evidence, ethical debates, regulatory perspectives, and payer considerations surrounding single-enantiomer drugs. We explore whether single enantiomers truly offer meaningful advantages -or if the reality is more nuanced.<\/p>\n\n\n\n<p class=\"has-ast-global-color-0-color has-text-color has-link-color has-medium-font-size wp-elements-3 wp-block-paragraph\"><strong>The Theoretical Advantages of Single Enantiomers<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">From a scientific standpoint, several <strong>theoretical benefits<\/strong> favor single-enantiomer development:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Target specificity<\/strong>: A pure eutomer may interact more selectively with the desired biological target, minimizing off-target effects (Jamali &amp; Mehvar, 1994).<\/li>\n\n\n\n<li><strong>Reduced dose<\/strong>: If the distomer is inactive or counterproductive, eliminating it can lower the therapeutic dose.<\/li>\n\n\n\n<li><strong>Simplified pharmacokinetics<\/strong>: Single-enantiomer drugs can exhibit less interindividual variability.<\/li>\n\n\n\n<li><strong>Predictable metabolism<\/strong>: Avoiding stereoselective metabolism may simplify drug interactions and clearance.<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">Regulatory guidance, such as the FDA\u2019s 1992 Policy Statement, reflects these theoretical advantages but <strong>does not assume superiority<\/strong> without proof (FDA, 1992).<\/p>\n\n\n\n<p class=\"has-ast-global-color-0-color has-text-color has-link-color has-medium-font-size wp-elements-4 wp-block-paragraph\"><strong>What the Clinical Evidence Shows: Case-by-Case Evaluation<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Despite the appealing theory, <strong>clinical superiority of single enantiomers must be demonstrated empirically<\/strong> -and the <strong>results have been mixed.<\/strong><\/p>\n\n\n\n<p class=\"has-vivid-red-color has-text-color has-link-color wp-elements-5 wp-block-paragraph\"><strong>1. Esomeprazole vs. Omeprazole<\/strong><\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Findings<\/strong>: Esomeprazole (S-enantiomer) showed improved acid control and healing rates compared to omeprazole, particularly at standard doses (Andersson, 2001).<\/li>\n\n\n\n<li><strong>Conclusion<\/strong>: Clinically meaningful advantage achieved.<\/li>\n<\/ul>\n\n\n\n<p class=\"has-vivid-red-color has-text-color has-link-color wp-elements-6 wp-block-paragraph\"><strong>2. Levocetirizine vs. Cetirizine<\/strong><\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Findings<\/strong>: Levocetirizine demonstrated similar efficacy with slightly fewer sedative effects compared to cetirizine (Simons, 2004).<\/li>\n\n\n\n<li><strong>Conclusion<\/strong>: Modest advantage, particularly in side-effect profile.<\/li>\n<\/ul>\n\n\n\n<p class=\"has-vivid-red-color has-text-color has-link-color wp-elements-7 wp-block-paragraph\"><strong>3. Dexmethylphenidate vs. Methylphenidate<\/strong><\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Findings<\/strong>: Dexmethylphenidate enabled similar efficacy at half the dose (Quinn et al., 2007).<\/li>\n\n\n\n<li><strong>Conclusion<\/strong>: Dosing advantage, but clinical outcome similar.<\/li>\n<\/ul>\n\n\n\n<p class=\"has-vivid-red-color has-text-color has-link-color wp-elements-8 wp-block-paragraph\"><strong>4. Escitalopram vs. Citalopram<\/strong><\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Findings<\/strong>: Some studies suggest escitalopram (S-enantiomer) offers faster onset and greater symptom relief for depression (Burke et al., 2002).<\/li>\n\n\n\n<li><strong>Conclusion<\/strong>: Clinically significant in some patient populations.<\/li>\n<\/ul>\n\n\n\n<p class=\"has-vivid-red-color has-text-color has-link-color wp-elements-9 wp-block-paragraph\"><strong>5. S-ibuprofen vs. racemic ibuprofen<\/strong><\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Findings<\/strong>: Despite the S-enantiomer being active, racemic ibuprofen remains the clinical standard because the R-form undergoes metabolic chiral inversion in vivo (Lee &amp; Jamali, 2006).<\/li>\n\n\n\n<li><strong>Conclusion<\/strong>: No significant clinical difference justifying switch.<\/li>\n<\/ul>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"525\" src=\"https:\/\/chiralpedia.com\/blog\/wp-content\/uploads\/2025\/04\/Clinical-Evidence-Chiral-switch-1024x525.png\" alt=\"\" class=\"wp-image-7548\" srcset=\"https:\/\/chiralpedia.com\/blog\/wp-content\/uploads\/2025\/04\/Clinical-Evidence-Chiral-switch-1024x525.png 1024w, https:\/\/chiralpedia.com\/blog\/wp-content\/uploads\/2025\/04\/Clinical-Evidence-Chiral-switch-300x154.png 300w, https:\/\/chiralpedia.com\/blog\/wp-content\/uploads\/2025\/04\/Clinical-Evidence-Chiral-switch-768x393.png 768w, https:\/\/chiralpedia.com\/blog\/wp-content\/uploads\/2025\/04\/Clinical-Evidence-Chiral-switch-1536x787.png 1536w, https:\/\/chiralpedia.com\/blog\/wp-content\/uploads\/2025\/04\/Clinical-Evidence-Chiral-switch.png 1538w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/figure>\n\n\n\n<p class=\"has-ast-global-color-0-color has-text-color has-link-color has-medium-font-size wp-elements-10 wp-block-paragraph\"><strong>Regulatory Perspective: Clinical Benefit is Not Assumed<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>FDA<\/strong>, <strong>EMA<\/strong>, and other agencies emphasize:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Superiority must be <strong>demonstrated through clinical trials<\/strong>, not assumed based on purity.<\/li>\n\n\n\n<li>Improvements in <strong>pharmacokinetics<\/strong> or <strong>manufacturing control<\/strong> alone are insufficient without corresponding <strong>clinical outcomes<\/strong>.<\/li>\n\n\n\n<li>New marketing authorization for a single enantiomer often requires <strong>comparative efficacy data<\/strong>.<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">Regulatory submissions for chiral switches must thus include:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Randomized controlled trials (RCTs) vs. the racemate.<\/li>\n\n\n\n<li>Clinical endpoints showing statistically and clinically meaningful improvements.<\/li>\n<\/ul>\n\n\n\n<figure class=\"wp-block-image aligncenter size-full is-resized\"><img loading=\"lazy\" decoding=\"async\" width=\"841\" height=\"756\" src=\"https:\/\/chiralpedia.com\/blog\/wp-content\/uploads\/2025\/04\/E7-01-visual-selection-1.png\" alt=\"\" class=\"wp-image-7559\" style=\"width:612px;height:auto\" srcset=\"https:\/\/chiralpedia.com\/blog\/wp-content\/uploads\/2025\/04\/E7-01-visual-selection-1.png 841w, https:\/\/chiralpedia.com\/blog\/wp-content\/uploads\/2025\/04\/E7-01-visual-selection-1-300x270.png 300w, https:\/\/chiralpedia.com\/blog\/wp-content\/uploads\/2025\/04\/E7-01-visual-selection-1-768x690.png 768w\" sizes=\"auto, (max-width: 841px) 100vw, 841px\" \/><\/figure>\n\n\n\n<p class=\"has-ast-global-color-0-color has-text-color has-link-color has-medium-font-size wp-elements-11 wp-block-paragraph\"><strong>Ethical Considerations: Patient-Centered Perspective<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Beyond clinical data, ethical principles call for caution:<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>1. Benefit-Risk Balance<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">If the single enantiomer offers only marginal improvements but commands a much higher price, is it ethical to promote it over the generic racemate?<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>For instance, <strong>escitalopram<\/strong> offers modest benefits over citalopram, but at a significantly higher cost -raising affordability concerns (Burke et al., 2002).<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>2. Informed Consent<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Patients must be informed when switching from a racemate to a single-enantiomer drug:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Differences in efficacy.<\/li>\n\n\n\n<li>Differences in side-effect profiles.<\/li>\n\n\n\n<li>Differences in cost.<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">Transparency is key to maintaining trust.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>3. Market Exclusivity and Access<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Chiral switches can delay generic competition if framed as new drugs, leading to prolonged periods of higher prices -a concern for health equity advocates (Agranat &amp; Wainschtein, 2010).<\/p>\n\n\n\n<figure class=\"wp-block-image aligncenter size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"445\" src=\"https:\/\/chiralpedia.com\/blog\/wp-content\/uploads\/2025\/04\/Ethical-Considerations-1-1024x445.png\" alt=\"\" class=\"wp-image-7552\" srcset=\"https:\/\/chiralpedia.com\/blog\/wp-content\/uploads\/2025\/04\/Ethical-Considerations-1-1024x445.png 1024w, https:\/\/chiralpedia.com\/blog\/wp-content\/uploads\/2025\/04\/Ethical-Considerations-1-300x131.png 300w, https:\/\/chiralpedia.com\/blog\/wp-content\/uploads\/2025\/04\/Ethical-Considerations-1-768x334.png 768w, https:\/\/chiralpedia.com\/blog\/wp-content\/uploads\/2025\/04\/Ethical-Considerations-1.png 1462w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/figure>\n\n\n\n<p class=\"has-ast-global-color-0-color has-text-color has-link-color has-medium-font-size wp-elements-12 wp-block-paragraph\"><strong>Payer and Health System Perspectives<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Payers -including insurance companies and public health systems -increasingly scrutinize the <strong>cost-benefit<\/strong> of single-enantiomer drugs:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Value-based coverage<\/strong>: Coverage decisions are now often based on comparative effectiveness studies.<\/li>\n\n\n\n<li><strong>Step therapy<\/strong>: Some payers require patients to try (and fail) generic racemates before approving single-enantiomer versions.<\/li>\n\n\n\n<li><strong>Formulary decisions<\/strong>: Drugs offering only marginal benefits may be placed on higher co-pay tiers.<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">Thus, even if regulators approve a single enantiomer, <strong>real-world utilization depends on demonstrated value<\/strong>.<\/p>\n\n\n\n<p class=\"has-ast-global-color-0-color has-text-color has-link-color has-medium-font-size wp-elements-13 wp-block-paragraph\"><strong>Factors That Favor Clinical Adoption of Single Enantiomers<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Single enantiomers tend to be favored clinically when they:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Offer <strong>clearly superior therapeutic outcomes<\/strong>.<\/li>\n\n\n\n<li>Significantly <strong>reduce side effects<\/strong> or improve safety.<\/li>\n\n\n\n<li>Simplify <strong>dosing regimens.<\/strong><\/li>\n\n\n\n<li>Show <strong>reduced variability<\/strong> across patient populations.<\/li>\n\n\n\n<li>Address <strong>unmet medical needs<\/strong> not fully satisfied by the racemate.<\/li>\n<\/ul>\n\n\n\n<figure class=\"wp-block-image aligncenter size-large is-resized\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"691\" src=\"https:\/\/chiralpedia.com\/blog\/wp-content\/uploads\/2025\/04\/E7-01-visual-selection-1024x691.png\" alt=\"\" class=\"wp-image-7557\" style=\"width:678px;height:auto\" srcset=\"https:\/\/chiralpedia.com\/blog\/wp-content\/uploads\/2025\/04\/E7-01-visual-selection-1024x691.png 1024w, https:\/\/chiralpedia.com\/blog\/wp-content\/uploads\/2025\/04\/E7-01-visual-selection-300x202.png 300w, https:\/\/chiralpedia.com\/blog\/wp-content\/uploads\/2025\/04\/E7-01-visual-selection-768x518.png 768w, https:\/\/chiralpedia.com\/blog\/wp-content\/uploads\/2025\/04\/E7-01-visual-selection.png 1032w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">Without these advantages, clinicians often prefer <strong>lower-cost racemates<\/strong>, especially if outcomes are comparable.<\/p>\n\n\n\n<p class=\"has-ast-global-color-0-color has-text-color has-link-color has-medium-font-size wp-elements-14 wp-block-paragraph\"><strong>Examples Where Single Enantiomers Did Not Dominate<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Not all single-enantiomer launches have succeeded:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Arformoterol<\/strong> (R-enantiomer of formoterol): Despite some PK advantages, it did not dramatically outperform formoterol in COPD treatment.<\/li>\n\n\n\n<li><strong>Dextromethorphan<\/strong> (DM) versus racemic mixtures: DM remains the standard for cough suppression, despite theoretical advantages.<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">These cases highlight that <strong>scientific plausibility<\/strong> does not guarantee <strong>clinical success<\/strong>.<\/p>\n\n\n\n<p class=\"has-ast-global-color-0-color has-text-color has-link-color has-medium-font-size wp-elements-15 wp-block-paragraph\"><strong>Emerging Trends: Personalized Medicine and Chirality<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">As personalized medicine advances:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Pharmacogenomics<\/strong> will help identify subpopulations that might benefit more from single-enantiomer formulations.<\/li>\n\n\n\n<li><strong>Enantiospecific therapies<\/strong> might be developed directly based on genetic profiles, reducing the need for post-market chiral switches (Zhou, 2011).<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">Thus, the future of single enantiomers may be more <strong>precision-driven<\/strong>, rather than <strong>one-size-fits-all<\/strong>.<\/p>\n\n\n\n<p class=\"has-ast-global-color-0-color has-text-color has-link-color has-medium-font-size wp-elements-16 wp-block-paragraph\"><strong>Conclusion<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Single-enantiomer drugs represent an important advance in pharmaceutical science -but their clinical superiority over racemates cannot be assumed. Each case must be evaluated based on hard clinical data, careful ethical analysis, and clear benefit-risk assessment. Regulators, payers, prescribers, and patients all have critical roles in ensuring that when one mirror image replaces two, it truly reflects better healing.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">In the next episode, we will turn our attention to the <strong>ethical and economic dimensions<\/strong> of chiral drugs -exploring how regulatory decisions intersect with intellectual property, access, and trust.<\/p>\n\n\n\n<p class=\"has-vivid-red-color has-text-color has-link-color wp-elements-17 wp-block-paragraph\"><strong>What is in the next episode?<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><em>&#8220;Beyond molecules and mirrors lies money and meaning. Join us for <mark style=\"background-color:rgba(0, 0, 0, 0);color:#d92929\" class=\"has-inline-color\">Episode 8: <strong>Beyond the Approval: Ethical and Economic Dimensions of Chiral Drugs<\/strong>.<\/mark>&#8220;<\/em><\/p>\n\n\n\n<p class=\"has-ast-global-color-0-color has-text-color has-link-color has-medium-font-size wp-elements-18 wp-block-paragraph\"><strong>&nbsp;References<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Israel Agranat &amp; Ilaria D\u2019Acquarica (2025), <em>Racemic drugs are not necessarily less efficacious and less safe than their single-enantiomer components<\/em>. European Journal of Pharmaceutical Sciences. <a href=\"https:\/\/doi.org\/10.1016\/j.ejps.2025.107082\">https:\/\/doi.org\/10.1016\/j.ejps.2025.107082<\/a> <\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Agranat, I., &amp; Wainschtein, S. R. (2010). The strategy of enantiomer patents of drugs. <em>Drug Discovery Today, 15<\/em>(5-6), 163\u2013170.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Andersson, T. (2001). Pharmacokinetics, metabolism and interactions of acid pump inhibitors: Focus on omeprazole, lansoprazole, pantoprazole, and rabeprazole. <em>Clinical Pharmacokinetics, 40<\/em>(7), 523\u2013538.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Burke, W. J., Gergel, I., &amp; Bose, A. (2002). Fixed-dose trial of the single isomer SSRI escitalopram in depressed outpatients. <em>Journal of Clinical Psychiatry, 63<\/em>(4), 331\u2013336.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Food and Drug Administration (FDA). (1992). <em>Development of New Stereoisomeric Drugs<\/em> (Policy Statement). Federal Register, 57(88), 22249\u201322250.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Jamali, F., &amp; Mehvar, R. (1994). Role of stereoselectivity in pharmacokinetics and pharmacodynamics. <em>Biochemical Pharmacology, 48<\/em>(4), 605\u2013616.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Lee, E. J., &amp; Jamali, F. (2006). Clinical pharmacokinetics of ibuprofen. <em>Clinical Pharmacokinetics, 6<\/em>(5), 402\u2013415.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Quinn, D., Bode, R., Bialer, P., &amp; The Focalin Study Group. (2007). Dexmethylphenidate hydrochloride versus methylphenidate in children with attention-deficit hyperactivity disorder. <em>American Journal of Psychiatry, 164<\/em>(5), 719\u2013725.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Simons, F. E. (2004). Advances in H1-antihistamines. <em>New England Journal of Medicine, 351<\/em>(21), 2203\u20132217.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Zhou, S. F. (2011). Drugs behave as substrates, inhibitors and inducers of human cytochrome P450 3A4. <em>Current Drug Metabolism, 9<\/em>(4), 310\u2013322.<\/p>\n\n\n\n<figure class=\"wp-block-embed is-type-wp-embed is-provider-chiralpedia wp-block-embed-chiralpedia\"><div class=\"wp-block-embed__wrapper\">\n<blockquote class=\"wp-embedded-content\" data-secret=\"h7IoWcoWaI\"><a href=\"https:\/\/chiralpedia.com\/blog\/racemates-%e2%89%a0-less-safe-rethink-chirality\/\">Racemates Less Safe. Rethink Chirality!<\/a><\/blockquote><iframe loading=\"lazy\" class=\"wp-embedded-content\" sandbox=\"allow-scripts\" security=\"restricted\" style=\"position: absolute; visibility: hidden;\" title=\"&#8220;Racemates Less Safe. Rethink Chirality!&#8221; &#8212; Chiralpedia\" src=\"https:\/\/chiralpedia.com\/blog\/racemates-%e2%89%a0-less-safe-rethink-chirality\/embed\/#?secret=UaPT8nTK3u#?secret=h7IoWcoWaI\" data-secret=\"h7IoWcoWaI\" width=\"500\" height=\"282\" frameborder=\"0\" marginwidth=\"0\" marginheight=\"0\" scrolling=\"no\"><\/iframe>\n<\/div><\/figure>\n","protected":false},"excerpt":{"rendered":"<p>&#8220;Science, ethics, and clinical outcomes converge at a difficult question -does the purer mirror image truly heal better?&#8221; Introduction The development of single-enantiomer drugs has been heralded as a leap forward in pharmacotherapy, promising greater efficacy, reduced side effects, and more predictable pharmacokinetics. But as the pharmaceutical industry increasingly embraced chiral switches and single-enantiomer innovations, &hellip;<\/p>\n<p class=\"read-more\"> <a class=\"\" href=\"https:\/\/chiralpedia.com\/blog\/episode-7-clinical-questions-are-single-enantiomers-always-better\/\"> <span class=\"screen-reader-text\">Episode 7: Clinical Questions: Are Single Enantiomers Always Better?<\/span> Read More &raquo;<\/a><\/p>\n","protected":false},"author":1,"featured_media":7726,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"site-sidebar-layout":"","site-content-layout":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"","ast-breadcrumbs-content":"","ast-featured-img":"","footer-sml-layout":"","theme-transparent-header-meta":"","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","footnotes":""},"categories":[7,43,116],"tags":[23,22],"class_list":["post-7253","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-chiral-science","category-chirality","category-regulatory-affairs","tag-chiral_drugs","tag-chirality"],"_links":{"self":[{"href":"https:\/\/chiralpedia.com\/blog\/wp-json\/wp\/v2\/posts\/7253","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/chiralpedia.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/chiralpedia.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/chiralpedia.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/chiralpedia.com\/blog\/wp-json\/wp\/v2\/comments?post=7253"}],"version-history":[{"count":18,"href":"https:\/\/chiralpedia.com\/blog\/wp-json\/wp\/v2\/posts\/7253\/revisions"}],"predecessor-version":[{"id":7765,"href":"https:\/\/chiralpedia.com\/blog\/wp-json\/wp\/v2\/posts\/7253\/revisions\/7765"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/chiralpedia.com\/blog\/wp-json\/wp\/v2\/media\/7726"}],"wp:attachment":[{"href":"https:\/\/chiralpedia.com\/blog\/wp-json\/wp\/v2\/media?parent=7253"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/chiralpedia.com\/blog\/wp-json\/wp\/v2\/categories?post=7253"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/chiralpedia.com\/blog\/wp-json\/wp\/v2\/tags?post=7253"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}