Biotech Currents

Biotech Currents

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Biotech Currents
Biotech Currents
ImmunoGen soars on ovarian cancer data: ~336% return from report price, ~153% blended return | $IMGN

ImmunoGen soars on ovarian cancer data: ~336% return from report price, ~153% blended return | $IMGN

SanaCurrents forecast positive results from the MIRASOL trial in an April 2023 report, expecting Elahere would perform better than chemotherapy in progression free survival, the trial’s key endpoint.

Bill Langbein
May 08, 2023
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Biotech Currents
Biotech Currents
ImmunoGen soars on ovarian cancer data: ~336% return from report price, ~153% blended return | $IMGN
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Before the market opened on May 3, ImmunoGen (NASDAQ:IMGN) reported overwhelmingly compelling results from its phase III confirmatory MIRASOL trial testing Elahere (mirvetuximab soravtansine-gynx) as a treatment for folate receptor alpha (FRα)-positive platinum-resistant ovarian cancer patients. The company’s stock then rose approximately 147% on May 3, 2023.

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SanaCurrents forecast positive results* from the MIRASOL trial in an April 2023 report, expecting Elahere would perform better than chemotherapy in progression free survival (PFS), the trial’s key endpoint. Elahere met the expected PFS statistical bar, but also exceeded it. Analysts had expected a 1.5-month median PFS advantage for Elahere compared to a projected 3.5 months for chemotherapy, according to a published report. ImmunoGen reported Elahere achieved a median PFS of 5.6 months compared to a higher than expected 4 months for chemotherapy.

The added fuel to the stock rise, however, was the surprising data in the overall survival (OS) rate. Elahere cut the risk of death for ovarian cancer patients by 33% (p=0.0046) compared to chemotherapy. The 33% reduction in MIRASOL was 10 percentage points higher than ImmunoGen’s previous Elahere trial, named Soraya.

At the time of the April 14 SanaCurrents report, ImmunoGen traded at $4.04 per share. On April 25, SanaCurrents exited part of its position in ImmunoGen but maintained coverage of the Elahere trial catalyst. ImmunoGen shares reached a high of $13.61 per share on May 3, reflecting an approximate 336%  return from the April 14 price. After placing about half of its ImmunoGen shares in a SanaCurrents pullback portfolio on April 25, the blended ImmunoGen return would be approximately 153%.

Seller’s remorse for SanaCurrents? Absolutely. And then some. SanaCurrents, however, forecasts a positive outcome for the catalysts it selects. Compelling data, such as the OS rate from the Elahere, can push returns much higher. At the same time, disappointing data can cause shares to sink rapidly.

The MIRASOL data indicate Elahere could shut the door on a potential competitor from Sutro Biopharma, Inc. (NASDAQ:STRO), enabling analysts to quickly revise projected sales for Elahere. Such revisions likely attracted more investors and boosted ImmunoGen’s stock price in the days after the release. ImmunoGen naturally capitalized on the data and said it would raise $200 million in a financing, temporarily tempering the stock’s ascent.

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* Original report available up request after upgrade to an annual or founding member plan. If you’ve already subscribed and would like a copy, please contact us immediately.

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