Given: For N drugs, M interaction similarities Sm, a small subset of known interactions yjj for pairs $ij\in \mathrm{ℒ}\subset \mathcal{P}$,

Learn: A kernel Z ⪰ 0, and interaction similarity combination weights αm ≥ 0, ${\displaystyle {\sum }_{m=1}^M{\alpha }_m=1}$,

Predict/Discover: Previously unknown pairwise drug-drug interactions ${\widehat{y}}_{ij}=\text{sign}(z_{ij})$, for pairs $ij\in \mathcal{U}=\mathcal{P}\backslash \mathrm{ℒ}$.