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Arsenic is a well-known poison, but arsenic trioxide is also a leukemia treatment.
| Symbol | As |
|---|---|
| Atomic number | 33 |
| Standard atomic weight | 74.92159 |
| Group | 15 |
| Period | 4 |
| Block | p-block |
| Category | Metalloid |
| Standard state | Solid |
| Discovered | Ancient |
Source: PubChem, Arsenic (periodic table data, retrieved 2026-10-19). Group and period follow the standard 18-column periodic table.
Shen and colleagues gave arsenic trioxide to 15 patients with relapsed acute promyelocytic leukemia; 9 of 10 treated with it alone reached complete remission, without bone-marrow suppression.
As reported in: Shen, Chen, Ni et al. (1997). Use of Arsenic Trioxide (As2O3 ) in the Treatment of Acute Promyelocytic Leukemia (APL): II. Clinical Efficacy and Pharmacokinetics in Relapsed Patients. Blood. doi:10.1182/blood.v89.9.3354
Abstract only
In a phase 3 trial in low-to-intermediate-risk acute promyelocytic leukemia, all-trans retinoic acid plus arsenic trioxide gave 97% two-year event-free survival versus 86% with retinoic acid plus chemotherapy, with less blood toxicity but more liver toxicity.
As reported in: Lo-Coco, Avvisati, Vignetti et al. (2013). Retinoic Acid and Arsenic Trioxide for Acute Promyelocytic Leukemia. New England Journal of Medicine. doi:10.1056/nejmoa1300874
Found by name, common compounds and chemical formulas in each entry.
Search Google Patents for arsenic in biological and medical uses: all patents · recent applications (2022+)
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