- Small pharmaceutical developer Aeterna Zentaris has scrapped its lead cancer candidate after the drug failed a late-stage study, sending the company's shares into a free fall on Monday.
- Aeterna Zentaris was testing Zoptrex (zoptarelin doxorubicin) — which pairs the synthetic, protein transporter zoptarelin with a cytotoxic payload of doxorubicin — in 512 women with locally advanced, metastatic or recurrent endometrial cancer who were resistant to platinum/taxane-based chemotherapy.
- Median overall survival (OS) periods were not significantly different between patients taking Zoptrex and those receiving doxorubicin monotherapy, clocking in at 10.9 months and 10.8 months, respectively, across the two groups. Aeterna Zentaris' treatment also missed secondary endpoints of clinical benefit rate, overall response rate and progression-free survival, and had a safety profile on par with the comparator arm.
Optimism in Zoptrex's future appears to have fizzled in the wake of the Phase 3 failure. In a May 1 statement, Aeterna Zentaris CEO David Dodd said the company would not explore any other indications for the drug, which the company also investigated as a treatment for prostate cancer. (A Phase 2 trial for breast cancer patients was attempted, but never completed due to poor recruitment.)
Zoptrex's shelving is especially devastating for Aeterna Zentaris because there isn't much else to fall back on. The drug was one of the just two clinical-stage assets the company had in its pipeline, with the other being the adult growth hormone deficiency (AGHD) treatment Macrilen (macimorelin).
While Macrilen has also made it through late-stage testing, the therapy lost much of its luster a few years ago when the Food and Drug Administration rejected it. Aeterna Zentaris revealed on Nov. 6, 2014, that the agency issued a complete response letter explaining the drug did not meet the primary objectives set forth in a Special Protocol Assessment, and called out the company for not providing the necessary diagnosis data for the trial's AGHD participants.
With the rest of the specialty pharma's pipeline consisting of pre-clinical and discovery-stage candidates, there aren't many other routes that would lead to a marketed product in the near-term.
"Our focus has now shifted entirely to filing our new drug application for Macrilen and, if the product is approved, to its commercial launch as soon as possible," Aeterna Zentaris' CEO David Dodd said in a May 1 statement. "We will also optimize our resources to be consistent with our focus on Macrilen-related efforts."
Dodd added his company plans to resubmit a New Drug Application for Macrilen in the third quarter of this year, and commercially launch the product in early 2018 should it get the FDA go-ahead.
Investors clearly weren't optimistic about this strategy or Zoptrex's failure. Stock fell about 60% to $1.35 by close of market Monday, down from $3.35 per share closing on April 28.
Drug manufacturer Ergomed, which partnered on Zoptrex development and trades on the London Stock Exchange, also saw shares down about 6% on May 2. The company was quick to distance itself from the trial failure.
"While it is obviously disappointing that this Zoptrex trial was not successful — especially for our partner Aeterna Zentaris — it does highlight the resilience of our hybrid business model," Ergomed CEO Miroslav Reljanovic said in a May 2 statement.
"Success for Ergomed does not hinge on just one asset, but rather the overall potential of a diversified development pipeline."