A British investor has injected another $40 million into Northwest Biotherapeutics, fueling the Maryland company’s increasingly promising pursuit of new vaccine therapies targeting both operable and inoperable cancers.

Neil Woodford, through his investment venture Woodford Equity Income Fund, will purchase roughly 5 million shares of Northwest Bio’s stock at $7.40 per share, totaling $40 million, the company announced this week. This latest infusion follows a $25 million stake Woodford took in the Bethesda-based company in September and, through a series of smaller stock purchases over the past year, brings his investment firm’s total stake in Northwest Bio near $100 million.

Woodford’s portfolio includes large stakes in some of the world’s biggest pharmaceutical companies, such as AstraZeneca and GlaxoSmithKline.

“This gives us the resources we need to ramp up our programs, and it will help us advance both of our two major product lines,” Linda Powers, chief executive at Northwest Bio, said in an interview.

Those two product lines consist of cell-based vaccines that the company, which was founded in 1996, has developed to harness the body’s immune system to attack solid cancer tumors. One of those treatments is intended to fight cancers — particularly brain cancer — that can be surgically removed. That product is currently in late-stage trials, and the tests are scheduled to conclude next year.

Meanwhile, Northwest Bio is in the earlier stages of testing vaccines to treat inoperable cancers — ones surgeons cannot go in and extract.

This latest financing round comes less than a week after the company presented data in Munich, Germany showing that a recent trial featuring 51 brain cancer patients showed significantly longer-than-expected survival for those receiving the former treatment (for operable cancers). The treatment showed success even with some of the most aggressive types of cancers.

“That’s obviously very exciting, both for us and for patients,” Powers said. “It has been a long road, but we’re nearing the finish line.”

Often, potential successes like this in the biotech sector capture the attention of the industry’s largest players, making Northwest Bio a possible acquisition target. However, Powers says being bought out isn’t the ideal plan.

“That’s always a possible road forward,” she said when asked about the likelihood of an acquisition. “But when there’s a whole new category of medical technology that didn’t exist before, which is what we believe we have with these immune therapies, there’s an opportunity to build the dominant player in that new category.”

She added: “Our preference — and we think we are positioned to have a real shot at this — would be to become that new dominant player.”

Follow J.D. Harrison and On Small Business on Twitter.