|
 The therapeutic goal is to provide HIV-positive patients with a similar type of genetic resistance to HIV that occurs naturally in 1% of the European population. By treating a patient's own stem cells and T cells (cells specifically targeted by HIV), we aim to protect patients from the ravages of AIDS and eliminate the need for daily medication.
A NATURALLY OCCURRING MODEL
In 1996 scientists determined that CCR5 is the primary co-receptor used by HIV to infect cells. Most people inherit two normal copies (one from each parent) of the gene that codes for the CCR5 protein. About 1% of the European population however, has a mutation in both copies (called homozygous) and thus do not produce any CCR5. These individuals are resistant to HIV infection and appear to suffer no ill effects from the absence of this receptor protein. Additionally, those individuals who have the mutation in only one copy (heterozygous) become infected with HIV, but have approximately half the CCR5 protein on the surface of their cells, and experience a 3-5 year delay in the progression of the disease.
MAJOR BREAKTHROUGH
In early 2007, an HIV-positive, leukemia patient in Berlin needed a bone marrow transplant to survive. Dr. Gero Hutter (one of Calimmune's clinical advisors) chose to use compatible marrow from one of the rare individuals who are naturally resistant to HIV in an effort to eradicate both diseases at once. Sixty-one days after the patient's transplant, his virus levels were undetectable, and they've stayed that way for over 3 years without the use of antiretroviral treatment. AmFAR recently declared the patient “functionally cured.” Although successful, this approach is impractical and too risky for widespread use. Instead of searching for a rare donor and then subjecting a patient to the rigors of a bone marrow transplant, Calimmune plans to replicate this natural resistance by treating a HIV-infected patient's own cells with an innovative gene-based cell therapy.
OUR PROPRIETARY TECHNOLOGY
Dr. David Baltimore, Nobel Laureate and now President Emeritus of the California Institute of Technology, suggested in a Nature journal article over a decade ago, that gene therapy could provide a possible treatment for HIV/AIDS if the genes that block HIV production could be transferred into blood stem cells (precursors to T cells). HIV-resistant T cells could then be produced by these individuals to maintain the immune/blood system, allowing the body to fight off infections and cancers, increasing one's quality of life, reducing the need for antiretrovirals and thereby eliminating the mortality associated with HIV/AIDS. Since then, Dr. Baltimore, and his esteemed colleagues have pioneered a blood stem cell therapy that blocks the expression of CCR5, used by HIV to enter T cells. Because of the rapid ability of HIV to develop resistance to monotherapy, the Calimmune team has included additional proprietary technologies to prevent HIV entry. The treatment is aimed at controlling and preventing HIV from progressing to AIDS. Armed with proof-of-concept, and safety/efficacy data, Calimmune continues to enhance the technology and is now in conversations with the FDA to take the first generation therapy of this innovative approach to the clinic. If successful, the one-time treatment can not only help HIV infected individuals, but it would also be a benefit to uninfected people. With reductions in viremia in infected individuals, this translates into a reduction in the community burden of HIV infection and that, in turn, has the ability to reduce the overall rate of new infections worldwide. |