ENTA's royalties on Glecaprevir/Pibrentasvir (G/P) are technically based on sales of the Glecaprevir portion of the regimen, which is contractually deemed to be 50%. Since ENTA's Glecaprevir royalty is tiered from 10%-20%, it's effectively a tiered 5-10% royalty on ABBV's sales of G/P.
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