Sibia Inc., a privately held La Jolla, Calif., companyfounded by the Salk Institute for Biological Studies in1981, has received two U.S. patents that it said broadlycover screening drugs for their ability to promote orinhibit activity on cell surface receptors and ion channels.

Michael Harpold, Sibia's chief financial officer and a co-inventor of the technology, said any public and privatesector researchers testing drugs on cellular receptors withassays that measure transcription-based functional signalscould be infringing Sibia's patents.

"We know of well over a dozen companies using thistechnology today," said Sibia's chairman and CEO,William Comer.

The patents, numbered 5,401,629 and 5,436,128, alsowere filed in Europe, Japan and elsewhere in the world.

Harpold said Sibia's patent protection extends toscreening compounds for activity on just about allreceptors _ including ion channels, growth factors and Gprotein couplers. The technology allows researchers todetect intracellular transduction of a signal generated byinteraction of a drug with the cell surface protein.

Harpold said Sibia's technology measures a compound'sability to influence the function of the receptors, not justbinding effectiveness. That means potential agonist andantagonist compounds can be evaluated.

Ronald Evans, a Salk Institute scientist with expertise inintracellular receptors and a member of Sibia's advisoryboard, said the patents are important because they formthe basis for screening compounds for activity on thehundreds of receptors that have been cloned.

The technology, he said, "allows you to convert a cell thatis receptor negative to receptor positive by introducingthe cDNA for the receptor." With the receptor clones, headded, "you can engineer the cells any way you want soyou can design the screening process to your needs."

For example, Evans said, by introducing to a cell theclone for a certain glutamate receptor type, the cellbecomes glutamate receptor positive and compounds canbe screened for activity to that specific receptor.

Glutamate receptors are involved in transmittingchemical messages among neurons and researchersbelieve the receptors are involved in numerous centralnervous system disorders, such as Alzheimer's andParkinson diseases.

"There are many glutamate receptors," Evans observed,"and here you can engineer a cell to express any specificglutamate receptor type and then test compounds on thatreceptor. You also could have cells with other glutamatereceptor types to see if the compounds affectcombinations of receptors."

Comer said Sibia, which is developingneuropharmaceuticals, used the technology to find acompound that is in preclinical development as atreatment for Parkinson's disease.

Sibia also has corporate partnerships with Eli Lilly andCo., of Indianapolis, and Switzerland-based Ciba-GeigyLtd. that utilize the patented technology.

In the Lilly collaboration, Sibia is testing compounds foractivity on neuronal voltage-gated calcium channels.With Ciba-Geigy, the focus is on excitatory amino acidreceptors.

The patents, Comer said, should help Sibia expand itscorporate collaborations. As for other companies usingthe technology, he said, Sibia will send "friendly letters"to them to initiate licensing negotiations. n

-- Charles Craig

(c) 1997 American Health Consultants. All rights reserved.