OLMA Stock Soars 47% in September So Far on Second PFE Deal

Shares of Olema Pharmaceuticals OLMA have rallied 46.5% so far in September after the company announced a new collaboration agreement for its lead product candidate, palazestrant, with pharma bigwig Pfizer PFE earlier this month. OLMA’s palazestrant is a proprietary, orally available small molecule with a novel mechanism of action.

Per the deal, the companies will conduct a phase Ib/II study to assess the safety and potential combinability of palazestrant with atirmociclib, Pfizer’s investigational, highly selective CDK4 inhibitor, in patients with ER+/HER2- metastatic breast cancer (MBC).

The impending phase Ib/II study evaluating the palazestrant-atirmociclib combo is expected to enroll approximately 35 patients, with initiation anticipated by the end of 2025. Subject to its success, Olema Pharmaceuticals expects the results to inform a potentially pivotal phase III study of the novel combination in the frontline MBC setting.

Year to date, OLMA stock has soared 37.2% compared with the industry’s 4% growth.

Per the agreement, Pfizer will provide atirmociclib for the phase Ib/II study, while Olema Pharmaceuticals will lead the study. Both companies will share ownership of clinical data and inventions arising from the combination study, though OLMA will retain exclusive global commercial and marketing rights to palazestrant.

The latest collaboration deal marks Olema Pharmaceuticals’ second partnership agreement with Pfizer, the first being signed in 2020. The companies are also evaluating the safety and tolerability of palazestrant in combination with Pfizer’s proprietary CDK4/6 inhibitor, Ibrance (palbociclib), in an ongoing phase Ib/II study in patients with recurrent, locally advanced or metastatic ER+/HER2- breast cancer. PFE’s Ibrance is currently approved for treating adults with HR+/HER2- MBC across several geographies.

OLMA’s Other Pipeline Development Activities

Olema Pharmaceuticals is also evaluating palazestrant as a monotherapy in a pivotal phase III OPERA-01 study for second/third-line ER+/HER2- MBC. In the second quarter of 2025, OLMA selected the 90mg of once-daily palazestrant as the dose for Part 2 of the OPERA-01 study. The company expects to share top-line data from this late-stage study in the second half of 2026.

Olema Pharmaceuticals, in partnership with Novartis NVS, is also evaluating palazestrant in combination with NVS’ Kisqali (ribociclib) in an ongoing phase Ib/II study to treat ER+/HER2- MBC. The company has already reported positive efficacy data from the early to mid-stage MBC study. Based on such data, OLMA and NVS are gearing up to initiate a pivotal phase III OPERA-02 study to evaluate the palazestrant/Kisqali combo in front-line ER+/HER2- MBC.

Under its agreement with Novartis, Olema Pharmaceuticals will receive Kisqali supply for the OPERA-02 study. In the second quarter of 2025, OLMA selected 90mg of once-daily palazestrant as the study dose, with its initiation expected soon and top-line data anticipated in 2028. Novartis’ Kisqali is currently approved as a monotherapy and in combinations for certain types of MBC across several geographies.

Additionally, Olema Pharmaceuticals is also evaluating palazestrant in combination with a PI3Ka inhibitor and with an mTOR inhibitor in two separate phase I/II studies for ER+/HER2- MBC.

OLMA also has a second investigational candidate, OP-3136, a novel, orally available small molecule that potently and selectively inhibits KAT6, in its early-stage pipeline. The company is currently enrolling patients in a phase I study evaluating the safety, tolerability, pharmacokinetics, pharmacodynamics and preliminary efficacy of OP-3136, as a monotherapy and in combination with AstraZeneca’s AZN Faslodex (fulvestrant) and palazestrant, in patients with advanced solid tumors. AZN’s Faslodex is also currently approved as a monotherapy and in combinations for several MBC indications globally.

Olema Pharmaceuticals anticipates initial phase I results for OP-3136 in 2026, with additional data in 2027 and a potential phase III study starting in 2028. The company estimates the global second/third-line ER+/HER2 metastatic breast cancer market opportunity for OP-3136 at around $5 billion.

Olema Pharmaceuticals, Inc. Price and Consensus

Olema Pharmaceuticals, Inc. price-consensus-chart | Olema Pharmaceuticals, Inc. Quote

OLMA’s Zacks Rank

Olema Pharmaceuticals currently carries a Zacks Rank #3 (Hold). You can see the complete list of today’s Zacks #1 Rank (Strong Buy) stocks here.

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