What happened

Novocure (NVCR -0.88%) stock dropped 10.3% in March, according to data from S&P Global Market Intelligence. For context, the S&P 500 returned 1.9% last month.

Despite this decline, shares of the maker of a device for treating brain cancer with electric fields have gained 38.3% in 2019, and are up a whopping 126% over the last year through April 5. 

Man sitting at desk wearing Novocure's Optune, which appears like netting on his head and includes an over-the-shoulder attachment attached to the head device.

Image source: Novocure.

So what

We can probably attribute a part of Novocure stock's pullback last month to its announcement on March 21 that Chief Science Officer Eilon Kirson will retire after about 7 years in the role, and 17 years with the company. Shares declined 5.9% on March 22. In its press release, the company said: 

The leadership transition presents an opportunity for Novocure to separate responsibility for medical and scientific affairs, ensuring appropriate focus as the clinical platform continues to expand. Effective immediately, Dr. Uri Weinberg, Novocure's Vice President of Clinical Development, will assume responsibilities for preclinical and clinical development and regulatory affairs. Effective April 1, 2019, Dr. Ely Benaim will join Novocure as Chief Medical Officer and will assume responsibilities for clinical operations, medical affairs and medical safety.

That said, a portion of the pullback is likely due to no particular reason other than investors taking some profits off the table. After all, this is a stock that has run up fast, as outlined above and as shown in the following chart. 

NVCR Chart

Data by YCharts.

Shares have risen due to investor optimism about the Jersey-based company's novel therapy for treating solid tumors with electric fields, Tumor Treating Fields, or TTFields. As I previous wrote, its "Optune device is currently approved by the U.S. Food and Drug Administration (FDA) to treat adults with glioblastoma, the most common primary brain cancer in adults and one of the most difficult cancer types to treat. Investors are hopeful that the company's addressable market will expand to include other types of cancers." 

Indeed, on March 22, Novocure announced that it has initiated "a phase 3 pivotal trial testing the efficacy of Tumor Treating Fields combined with paclitaxel in patients with recurrent, platinum-resistant ovarian cancer." This is the company's fourth phase 3 pivotal trial initiated to study solid tumors beyond glioblastoma. 

Now what

Investors should soon be getting material news. Novocure is slated to report its first-quarter 2019 results on Thursday, May 2, before the market opens.