Street View: Arvinas' breast cancer drug's trial results a letdown

Pfizer PFE.N and Arvinas' ARVN.O experimental treatment failed to delay progression of breast cancer in patients with the most common type of the disease in a late-stage trial

The smaller biotech's shares tumbled 53% to an all-time low on Tuesday

But the oral drug, vepdegestrant, helped to extend progression-free survival in a subgroup of participants with a specific gene mutation

'DEVIL IS IN THE DETAILS'

Jefferies ("Buy,"PT:$52) says it is lowering expectations of peak sales to ~434 mln from ~$600 mln

Oppenheimer ("Perform") says it would probably take an eye-opening hazard ratio (odds that a treated patient will resolve symptoms before a control patient) among the subset with the specific gene mutation to curry favor with investors - but the chances are increasingly small

BMO Capital Markets ("Outperform", PT:$20) says the benefit in the subgroup was anticipated, making the failure in the larger set of patients a "more meaningful let down"

Wedbush ("Neutral," PT:$12) says they have "less confidence" in the ability of vepdegestrant to differentiate as a combination therapy

Guggenheim ("Buy," PT: $57) sees "low visibility on vepdegestrant commercial potential" until full data presentation, but finds drug approval to be likely