Didier Drogba had fired the visitors ahead with a low drive three minutes into the second half but substitute Eren Derdiyok levelled with a far-post header in the 73rd minute.
Germany’s Leverkusen, who face Genk in their last group match in December, top the group on nine points, one ahead of Chelsea and Valencia.
The visitors had a first stab at the Leverkusen defence with Daniel Sturridge outpacing Michal Kadlec down the right but his cutback into the box was well handled by keeper 19-year-old keeper Bernd Leno.
After an opening 20-minute spell spent in a midfield tug-of-war the game gradually opened up with Leverkusen’s Michael Ballack, in his 100th European appearance, heading a corner onto the crossbar in the 32nd minute.
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