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    "story_id": "mp-2026-07-24-009",
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    "edition_id": "mp-2026-07-24-morning-0015",
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    "headline": "A Tighter Chemical Warhead Hits Fewer Bystanders",
    "slug": "a-tighter-chemical-warhead-hits-fewer-bystanders",
    "dek": "A bicyclobutane group preserved tumor-target binding while reducing unintended protein reactions in preclinical tests.",
    "summary": "A bicyclobutane group preserved tumor-target binding while reducing unintended protein reactions in preclinical tests.",
    "body_text": "Moffitt Cancer Center researchers designed a strained bicyclobutane chemical group that preferentially reacts with cysteine, then swapped it into existing covalent-drug scaffolds. A redesigned version of dacomitinib retained target activity, bound fewer unintended proteins, and controlled human lung tumors in mice about as well as the approved drug, with improved exposure and no obvious study toxicity. These are laboratory and animal results; human safety and benefit have not been established.",
    "why_it_matters": "A bicyclobutane group preserved tumor-target binding while reducing unintended protein reactions in preclinical tests.",
    "limitations": [
      "A redesigned version of dacomitinib retained target activity, bound fewer unintended proteins, and controlled human lung tumors in mice about as well as the approved drug, with improved exposure and no obvious study toxicity.",
      "These are laboratory and animal results; human safety and benefit have not been established."
    ],
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    "modified_at": "2026-07-24T09:28:00.000-04:00",
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        "text": "A bicyclobutane group preserved tumor-target binding while reducing unintended protein reactions in preclinical tests.",
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        "qualification": "A redesigned version of dacomitinib retained target activity, bound fewer unintended proteins, and controlled human lung tumors in mice about as well as the approved drug, with improved exposure and no obvious study toxicity."
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    "tags": [
      "cancer drugs",
      "covalent chemistry",
      "preclinical"
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    {
      "source_id": "source-2026-07-24-009",
      "title": "Moffitt Cancer Center via Newswise: Selective covalent drug chemistry",
      "publisher": "Moffitt Cancer Center via Newswise",
      "url": "https://www.newswise.com/articles/moffitt-scientists-pioneer-next-generation-covalent-chemistry-to-build-safer-precision-medicines",
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    "name": "The Machine Press",
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  "cite_this_report": {
    "title": "A Tighter Chemical Warhead Hits Fewer Bystanders",
    "publisher": "The Machine Press",
    "published_at": "2026-07-24T09:00:00.000-04:00",
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