New Haven, Conn.-based Kolltan Pharmaceuticals Inc., a private company developing monoclonal antibody (MAb) drugs that will target receptor tyrosine kinases (RTKs), has secured $60 million from a series D financing round, which will help support phase II trials of KTN3379, an inhibitor of the ErbB3 receptor tyrosine kinase, their lead dual-mechanism MAb candidate in cancer patients suffering from various malignancies.

“The RTK ErbB2, when overexpressed in a tumor, can use ErbB3 as a substrate, which serves to limit the utility of inhibitors of ErbB2,” Jerry McMahon, president and CEO of Kolltan, told BioWorld Today. “In addition, ERBB3 signaling, when activated by its ligand, neuregulin, limits the effectiveness of epidermal growth factor receptor [EGFR] inhibitors. This is what makes KTN3379 an exciting compound because it is designed to block activation of the ErbB3 RTK regardless of whether ErbB3 is being activated by its ligand, neuregulin, or by its association with other RTKs such as ErbB2.”

The clinical effects of ErbB receptor-targeting drugs in cancer treatment are limited due to a high frequency of resistance.

“We know ErbB3 increases its activity when patients with various tumors are treated with these cancer drugs and so by hitting this target the resistance can be dialed down making the medicines more effective,” McMahon added.

The financing will allow the company to vigorously move forward with its KTN3379 program. In addition, the company plans to accelerate the development of two additional undisclosed first-in-class biologic preclinical product candidates.

There are a number of tumor types where ErbB3 plays a role and a variety of combination treatment possibilities to consider. For this reason, McMahon said that they are putting a patient selection strategy in place using assessment of ErbB3 function in tumor biopsies. Part of their initial clinical trials will be to focus on identification of patients with a tumor type who would respond to the therapy or combo therapies.

Although there are a lot of considerations to take into account with this strategy, the company expects to have an initial phase II plan in place by the second half of this year.

“All three of our current programs are exciting and different but united by the common theme that we understand the biology and biochemistry of these RTKs; and we are creating products that will be useful for cancer and other diseases where we think the biology of these receptors is playing a role.”

The financing was led by a new undisclosed investor, a Boston-based global institutional asset manager, and by an existing investor, KLP Enterprises. The company also received strong participation from existing shareholder C.T. Koll LLC. Additional new investors participating in the round included Deerfield Management, Franklin Berger, and others. Existing investors in the financing included HBM Healthcare Investments Ltd., Purdue Pharma L.P., Osage University Partners and others.

In other financings news:

Akebia Therapeutics Inc., of Cambridge, Mass., said it closed its initial public offering (IPO) of 6.76 million shares of common stock priced at $17 per share. The total includes the exercise in full by the underwriters of their option to purchase 879,647 shares of common stock. The aggregate net proceeds are approximately $106.9 million. Morgan Stanley, Credit Suisse and UBS Investment Bank acted as joint book-running managers, and Nomura acted as a co-manager for the offering.

Dyax Corp., of Burlington, Mass., said the underwriters of its public offering have exercised in full their option to purchase an additional 1.2 million shares at $9.25 apiece. That brings the aggregate net proceeds from the offering to approximately $80 million.

Endocyte Inc., of West Lafayette, Ind., said it is offering to sell 4.5 million shares of its common stock in an underwritten public offering. The company expects to grant the underwriters a 30-day option to purchase up to an additional 675,000 shares of common stock. Pricing of the shares have not yet been set.

SCpharmaceuticals Inc., of Lexington, Mass., said it closed a $16 million series A financing round co-led by 5AM Ventures and Lundbeckfond Ventures. The proceeds will be used to further develop two pharmaceutical products and its associated drug delivery technology. The first product is a drug-device combination product based on the active ingredient furosemide, allowing for convenient “anytime anywhere” subcutaneous delivery. Furosemide currently requires intravenous administration when higher doses are temporarily necessary in the management of patients with heart failure. The second product is a new drug-device combination product of a cephalosporin antibiotic, currently only available for intramuscular and intravenous administration.