By Mary Welch

SuperGen Inc. raised $16.6 million in a private placement designed to help fund its clinical programs for rubitecan, now in Phase III trials, and Nipent, its approved leukemia drug that is being proposed for additional indications, as well as for other oncology programs.

About 1 million shares were sold at about $16.50 apiece, a 10 percent discount to the price when the deal was made. SuperGen's stock (NASDAQ:SUPG) closed Tuesday at $19.812, down 68.75 cents.

There are now between 22 million and 23 million shares outstanding.

"We wanted to raise about $15 million, and it's not easy to raise money these days," said Raj Shrotriya, executive vice president and chief scientific officer for the San Ramon, Calif.-based company. "But we got a very good deal. These people [Capital Research & Management Co.] came in and offered us a price we wanted. It was swift and the deal was done in one day. It was a no-brainer."

Capital Research & Management handled the transaction for the American Funds Group, both of San Francisco.

"Not only will these funds help us with rubitecan and Nipent, but it allows us to make sure our priorities are right and not dilute ourselves, our efforts," Shrotriya said. "It will allow us to look at what's in our pipeline and Sparta's pipeline and follow through properly."

Earlier this year SuperGen acquired Sparta Pharmaceuticals Inc., of Horsham, Pa., in a deal worth almost $7 million. SuperGen is particularly interested in Sparta's 5-FP, an oral drug that the liver converts into the cancer drug 5-FU; PZG, a compound for diabetes; and LEX 032, a cancer therapy, Shrotriya said. It also is especially interested in Sparta's Spartaject, which allows for the injection of water insoluble materials without the need for organic solvents, he said. (See BioWorld Today, Jan. 20, 1999, p. 1.)

SuperGen's lead candidate is rubitecan (formerly RFS 2000). Enrollment is continuing in three Phase III studies for pancreatic cancer. The company acquired the rights to the anticancer compound from the Stehlin Foundation for Cancer Research in Houston in 1997. The company expects to file a new drug application (NDA) sometime next year, Shrotriya said.

Rubitecan, a topoisomerase I inhibitor that is extracted from the bark and leaves of the camptotheca acuminata tree in China, showed in a Phase II study that median survival among responders exceeded 18 months. According to the May 1999 issue of the International Journal of Oncology, patients taking rubitecan showed the longest survival rate ever reported among pancreatic patients.

In addition, rubitecan is in clinical trials for other tumors, such as ovarian, head and neck, colorectal, breast, lung, cervical, prostate and gastric.

SuperGen believes rubitecan has use in other areas as well. In fact, preliminary Phase II study results showed rubitecan demonstrating some benefit in a Phase II study in patients with hematological diseases. Four of the 10 patients in the trial were diagnosed with chronic myelomonocytic leukemia; the other six with Philadelphia chromosome-negative, a myelodysplastic syndrome disease. (See BioWorld Today, Dec. 9, 1998, p. 1.)

"The way you maximize a drug in oncology is to get approval in one indication, which we hope will be pancreatic cancer. Then you get the doctors used to it and you get them to use the drug in different ways," said Shrotriya. "That's our strategy."

Nipent was licensed by SuperGen from American Home Products Corp., of Madison, N.J., in 1992 and posted 1998 sales of $3 million for hairy cell leukemia. Earlier this year, the company filed a supplemental new drug application to use Nipent to treat mature T-cell lymphomas, primarily cutaneous T-cell lymphoma and peripheral T-cell lymphoma. (See BioWorld Today, March 1, 1999, p. 1.)

Nipent is a small-molecule purine analogue that acts by blocking the enzyme adeonosine deaminase in cells, and doesn't require the presence of surface receptors.