02606nas a2200313   4500000000100000008004100001260004300042653002200085653001900107653001700126653001300143653002600156100001200182700001500194700001400209700001300223700001500236700001500251700001500266700001300281700001400294700001600308700001200324245015200336856010100488300001100589520166700600022002502267       2026                            d  c08/2026bOxford University Press (OUP)10aTrypanosoma cruzi10aChagas disease10aBenznidazole10aSerology10aResponse to treatment1 aSaade U1 aRamirez JC1 ade Boer J1 aBazan NA1 aMangone FM1 aRamadier T1 aScandale I1 aPottel H1 aAltcheh J1 aChatelain E1 aZrein M00aA serological method’s ability to distinguish treatment regimens by assessing early antibody decline in Chagas patients: insights from E1224 data  uhttps://academic.oup.com/jid/advance-article-pdf/doi/10.1093/infdis/jiag427/70701919/jiag427.pdf  a1 - 193 a<p><strong>Background</strong></p>

<p>No reliable markers exist for parasitological cure in adult patients with chronic Chagas disease. We assessed whether a serological multiplex immunoassay for Trypanosoma cruzi, MultiCruzi, could differentiate the outcomes of treatment regimens.</p>

<p><strong>Methods</strong></p>

<p>This analysis included adults with indeterminate Chagas disease from a randomized trial of E1224. Serum samples at baseline, 6, and 12 months post-treatment with Benznidazole, E1224 regimens, or placebo were tested at three dilutions using MultiCruzi. We calculated the dilution factor at which 50% of reactivity remained (DF50) and used mixed-effects models to assess antibody decline. Log2DF50 slopes compared Benznidazole and E1224 regimens, and pooled data from the BENDITA trials helped define a cut-off for treatment response.</p>

<p><strong>Findings</strong></p>

<p>Within six months after treatment, participants exhibited a significantly greater rate of decline in antibody levels compared to the placebo group, contrasting with results from T. cruzi conventional ELISA tests. Our analysis showed a difference in response to benznidazole and to E1224 regimens after twelve months’ follow-up, confirming results for benznidazole from BENDITA. Combining data from both trials allowed discrimination of benznidazole and E1224 treatment regimens after six months’ follow-up.</p>

<p><strong>Conclusion</strong></p>

<p>MultiCruzi enables the early assessment of treatment-associated biological responses in adults with Chagas disease, with antibody decline serving as an exploratory pharmacodynamic marker.</p>
  a0022-1899, 1537-6613