Argos Therapeutics’ hopes of winning approval for its cancer vaccine candidate rocapuldencel-T have taken a major blow. The independent monitoring committee recommended stopping the phase 3 trial for futility after getting a look at interim results, wiping 65% off Argos' stock and leaving it to scour through the data in search of a path forward for its lead candidate.
Durham, North Carolina-based Argos is leaving the study open while it digs through the data and discusses the results with FDA. But as it stands, rocapuldencel-T looks in dire danger of joining the ever-growing list of cancer vaccines to fall short in the clinic.
"We are extremely disappointed with these results, which included 75% of the targeted events needed to permit the primary analysis and assessment of overall survival in the study," Argos CEO Jeff Abbey said in a statement.
Argos is yet to disclose details of the results, beyond the telling top-line finding that the data committee ruled the rocapuldencel-T arm is unlikely to post a statistically-significant improvement in overall survival. Argos had hoped its cancer vaccine would prove a better option for metastatic renal cell carcinoma patients than Pfizer’s Sutent.
The failure of rocapuldencel-T to live up to Argos’ expectations is another black mark against the beleaguered cancer vaccine sector. Argos touts the platform underlying rocapuldencel-T, Arcelis, as a more precise approach to immunotherapy capable of coping with the genetic variability of solid tumors. Now, rocapuldencel-T risks becoming another example of a high-promise, poor-performing cancer vaccine, something the sector already has in abundance.
Argos raised money to fund the phase 3 privately and through an IPO for the trial while operating in the long shadow cast by Dendreon, which, like Argos, worked with a form of dendritic cell technology. In recent days, Argos and Agenus—which saw its cancer vaccine fail an interim review—have provided more ammunition for those skeptical about the effectiveness of the field.
For Argos, the failure continues its patchy record in the clinic. The biotech suffered a setback in 2015 when its HIV immunotherapy came up short in phase 2.
Fellow cancer biotech Agenus also had similarly bad news this week, disclosing in a SEC filing on Tuesday, 21 Feb. that a DSMB also looked poorly on its phase 2 trial of Prophage G-200 (Heat Shock Protein Peptide Complex-96 or HSPPC-96) vaccine in combo with Roche’s aging Avastin (bevacizumab) in patients with certain brain tumors.
“The interim analysis suggested that the trial is unlikely to demonstrate that the vaccine in combination with bevacizumab will lead to a better survival than bevacizumab as a monotherapy,” the DSMB said, via the SEC form. Agenus said given the board’s negative view, “the accrual for the trial has been closed.”
Argos was down 60% this morning on the news, trading around $1.75, while Agenus was down 5.3%.