understanding monoclonal antibodies
“When a bacteria or virus enters a creature’s body it can cause a lethal infection OR the body’s immune system can quickly make antibodies that effectively bind to the invaders. Then other cells destroy and remove them.
“Antibodies are made by B lymphocytes, a type of white cell that floats in the blood stream. Their surface membranes have receptors that recognize a great variety of different antigens from bacteria, viruses, and other disease-causing organisms. When they identify an invader the receptors secrete antibodies. The antibodies are produced in billions of forms, each with a different amino acid sequence and a different antigen-binding site. Once activated B cells clone themselves. They quickly produce a huge number of identical B lymphocytes and each new lymphocyte makes the same antibody. They also create memory cell and that allows them to react quickly if a similar virus or bacteria invades.
The new B cells start secreting antibody while they are still small, then they grow and turn into plasma cells and secrete antibodies at the astonishing rate of about 2000 molecules per second.”
https://www.ncbi.nlm.nih.gov/books/NBK26884
in 1951Henrietta Lacks, a 31-year old African-American woman was treated for or cervical cancer at Johns Hopkins Hospital in Baltimore, Maryland. During her treatment, cells from her tumor were taken and grown in the laboratory. Dubbed HeLa cells, they grew continuously and didn’t die. https://osp.od.nih.gov/hela-cells/significant-research-advances-enabled-by-hela-cells
Multiple myeloma (MM) is a clonal B-cell disorder characterized by the proliferation of malignant plasma cells. The cells are long lived—or perhaps eternal. By 1975 scientists had isolated 4 strains of undying mouse myeloma cells.
In the 1940s scientists started studying the soluble “factors” in pus and found proteins—cytokines-- that were produced by white blood cells; some caused fever, elevated white blood cell and migration of inflammatory cells. “We currently know of five major cytokine families. One family, TNF (tumor necrosis factor) has 20 members, each of which has its own gene. The interleukin cytokine family has over 30 known members, and they all have biological functions. There’s a lot of overlap.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3140102/
The story of the TNF cytokines and the creation of antibodies that block their action started in the 1960s and ’70s when a number of scientists developed mouse myeloma cells (malignant plasma cells) that could be grown in tissue culture and that, along with their progeny, survived indefinitely. They were said to be “immortal.”
Then a researcher named César Milstein, who was working at Cambridge, learned how to turn two small myeloma cells into one larger cell. Milstein was Jewish and was born in Argentina. His father had exited Russia when he was 14 years old. His mother was born in Argentina and was the head mistress of a school. She encouraged her son to study hard and go to the University of Buenos Aires. At one point, she helped type her son’s PhD thesis.
After he graduated, Milstein married and spent three years as a post-doc fellow at a lab in Cambridge, England. In 1961, he returned to Argentina and was supposed to head a department at the university, but the politics of the country had changed. A military coup had taken control of the government, and it was conducting a campaign against political dissenters and targeting Jews. When he was an undergraduate, Milstein had taken part in demonstrations against the country’s president, Juan Peron. He felt unsafe and returned to the lab at Cambridge and worked there. In 1974, he started working with Georges Köhler, a Swiss postgraduate researcher who was also interested in fusing myeloma cells.
That year, the two Cambridge researchers injected purified protein into a mouse. One of its lymphocytes recognized the invader and started cloning, making copies of itself. Each new lymphocyte predictably produced antibodies to the same foreign protein. After a few days, one of the researchers drew blood from the animal’s spleen. As expected, the serum was full of identical lymphocytes, each of which produced the same antibody. So far, nothing exceptional had happened.
At this point, the researchers attempted to fuse some of the lymphocytes to mouse myeloma cells, malignant plasma cells that don’t die. The combination was supposed to keep reproducing and keep making quantities of one and only one antibody.
As Köhler, a shy, gentle Swiss German immunologist, later explained, the fusion approach was new and unique. “If by blind chance the right lymphocyte, the one producing the antibody against the injected antigen, had fused with the myeloma cell and it was forming daughter cells that were locked into producing the same pure antibody . . . it was a long shot.” Around Christmas 1974, Köhler added the antigen to the fused antibody-producing cells and went home. If the experiment worked, the antibodies would combine with the antigens. They would precipitate, and halos would form around the cells. Köhler returned hours later, and, fearing failure, brought his wife along to console him. They looked in the window, saw the halos, and were elated. “I kissed my wife. I was all happy.”
The two researchers wrote a paper and told the world about the first “hybridoma”—part lymphocyte, part myeloma cell—the first “factory” that produced monoclonal antibodies. In the tradition of Howard Florey, the developer of penicillin, and Albert Sabin, the creator of the oral polio vaccine, the researchers did not patent their creation.
A few years later, a researcher named Hilary Koprowski, “a colorful, prominent Polish-born virologist,” used the monoclonal antibody procedure in his research and decided to patent the method.
Once he owned the process, Koprowski and an entrepreneur named Michael Wall formed a company named Centacor, and they tried to figure out how to turn mouse monoclonal antibodies into gold.
In the summer of 1982, Michael re-met Jan Vilcek, a man who worked at a New York hospital and studied cytokines. A Czech researcher, Jan was a six-year-old Jewish kid in 1938 when the British prime minister “gave” his country to Hitler in return for a promise of peace. During the next few years, the Nazis rounded up and killed Jews. Vilcek and his parents survived “because they had a complicated attitude toward their Jewishness.” At some point, they converted to Catholicism, changed their address, and Jan’s father joined the underground. One way or another, they managed to avoid the death camps.
After the Second World War, Russia took control of Czechoslovakia, and the country became part of the Eastern Bloc. The Soviet Union and the U.S. feared one another and built nuclear missiles. They maintained armies, restricted travel between the Soviet Bloc and the West, and forbade immigration.
Vilcek married and became an accomplished researcher. Two years after the first known cytokine, interferon, was identified, he started studying it. The cytokine got its name because it was secreted by infected cells. Interferon then made nearby cells resistant to the virus.
When he was in his 20s, fed up with the Czech Communist government, Vilcek decided to “relocate.” In 1964, he and his wife received permission to cross the iron curtain for a three-day vacation in Vienna. It was October and still warm. They traveled by auto and brought their heavy winter coats with them. When they reached the border, their car was searched. Jan worried that the coats would be a giveaway—that the inspectors would realize that he and his wife were trying to escape. He waited while the border guards “hesitated for the longest minutes of his life before letting them pass.” Once across the line that divided the countries, Vilcek and his wife didn’t go back. After the couple reached Germany, life was rough, but within a year, Vilcek was hired by NYU, New York University.
After spending a number of years studying interferon, Vilcek attended a workshop on a poorly understood immune regulator, a cytokine called tumor necrosis factor (TNF). In 1984, Genentech scientists determined and published the complete amino acid composition of the TNF cytokine. They purified the human protein and gave some of it to NYU. Vilcek and his colleagues accepted the gift and “felt like kids in a candy store—what should we try first?”
The cytokine turned out to play a role in a body’s ability to fight viral infections. It had so many additional actions that one of Vilcek’s graduate students quipped, “TNF should stand for too numerous functions.”
After cytokines are secreted by a cell, some bind to receptors on the surface of other cells and regulate the immune response. They sometimes work alone, sometimes together, and they can even work against one another.
In the 1970s, scientists learned how to alter the genetic makeup of mice. Genes are sequences of DNA. When a gene is injected into a fertilized mouse egg, the inserted DNA can become part of the mouse genome. When it is then passed from one generation to the next, it can instruct the mice to make certain proteins.
In the ’80s, Centacor (still struggling), on a whim, a hope, produced a monoclonal antibody that would block or inactivate TNF. It was made in a mouse that was genetically altered so its antibodies were “chimeric,” part human and part mouse. The development took experts at Centacor six months. The antibody’s patent was owned by Centacor and NYU (an independent private research university). The cytokine blocker didn’t (as Centacor had hoped) help people with sepsis. But it blocked the action of TNF, prevented a cascade of pro-inflammatory cytokines, and hindered inflammation.
When London doctors (Feldman and Maini) injected the medication into the swollen, inflamed joint of a person with rheumatoid arthritis, it helped for three months. A repeat injection was also successful. In 1993, a physician from Holland successfully used the antibody to treat a desperately ill 12-year-old girl with a severe case of Crohn’s disease, a chronic inflammation of the small and sometimes large bowel. The antibody was called infliximab and was approved by the FDA in 1998. It is currently a commodity, one of the treatments that are used to treat ulcerative colitis, rheumatoid arthritis, ankylosying spondylitis, and various manifestations of psoriasis.
Part of the research was funded by the NIH (the taxpayer) and part by Centacor. There was a lot of luck and serendipity along the way. Both Centacor and NYU were rewarded. In 1999, Johnson & Johnson bought Centacor for $4.9 billion. Revenues from the drug (per J & J) rose annually, and topped $7 billion in 2016.
Though the cytokine blocker helped, it was still immunologically part mouse. Industry felt it had to create a rodent whose antibodies were indistinguishable from those made by man.
Humira—adalimumab—is an antibody that blocks TNF. It was created in mice that were genetically modified in embryo to make antibodies that a person’s immune system thinks are human in origin. Some of the research on Humira was performed by researchers at the government-funded Cambridge Antibody Technology, U.K.
When the drug was approved by the FDA and was financially successful, scientists in many of the world’s labs knew how to make monoclonal antibodies to TNF. They couldn’t market them without performing placebo control studies that proved their drug was both safe and effective. That was costly, ethically questionable, and medically unnecessary.
Early in 2010, President Obama signed
the Biologics
Price Competition and Innovation Act of 2009. It allowed companies to market
“biological products”’ that were
demonstrated to be highly similar (i.e., biosimilar), and
basically interchangeable with an FDA licensed biological product. The biosimilars did not need to undergo
double blind control trials before they were approved by the FDA. But the original drug’s period of exclusivity
was twelve, not five years.
When Congress debated the proposed legislation, some argued that it takes a long time to develop a new biologic, and giving a product extra years will spur innovation. The dozen-year monopoly was opposed by generic manufacturers and consumer groups. They argued that 12 years meant biologics would likely be expensive and often unaffordable for too long.
Bruce Downey, the chairman of the Generic Pharmaceutical Association, argued the long period would negatively affect innovation. In much of Europe, biosimilars can be marketed as soon as they have been shown to perform as well as the original drug, but they are usually not thought of as interchangeable or a generic version of an existing medication. They are instead treated like a competitor or a therapeutic alternative. Outside of a small number of Eastern European countries, pharmacists can’t substitute a biosimilar for a designated medication without permission from the prescribing physician. Currently in France and Italy, and perhaps elsewhere, “biosimilar adoption rates have been low.”
Several cytokine families (including interferons) contain both pro- and anti- inflammatory molecules. Drugs that block cytokines are currently available to molecules that belong to one of two groups: “TNF—tumor necrosis factor” and “interleukins.”
High levels of a number of cytokines have been found in the blood of people with infiltrates in both lungs and low levels of blood oxygen caused by SARS, MERS, and COVID-19.
By late 2020 thirty-six interleukins had been identified, and pharmaceutical researchers had developed, tested, and marketed humanized monoclonal antibodies that block some of them.
Using a clause in the law to pressure competitors, the owners of Humira extended its 12 -year U.S. monopoly for an additional five years. Their action might have been the real reason for the congressional inquiry that was held on February 26, 2019.
The session in question was officially an investigation of drug prices. The senator chairing the session was Ron Wyden of Oregon. He focused his questions on Richard Gonzalez, the CEO of the company that makes and markets Humira.
Gonzalez had worked for Abbott Laboratories for 30 years. He was the current head of AbbVie, the Abbott spin-off that owned Humira. In 2007, he developed throat cancer and retired. His cancer was successfully treated, and when he recovered, he decided he would “go back and do something.” His company’s main moneymaker, Humira, was FDA approved in 2002, and it was given a 12-year monopoly. During that time, other manufacturers realized the drug was a gold mine and they developed generic biosimilars, drugs that worked as well but were chemically a little different.
When the 12-year monopoly drew to a close, AbbVie lawyers allegedly used “a patent thicket of overlapping and add-on patents as well as the litigation process itself, as a mechanism to protect its blockbuster.” The AbbVie legal team was prepared to initiate a court battle that could keep competitors off the market, but they started negotiating with the companies that had spent years and perhaps millions of dollars developing biosimilar medications. In the end, the competition was allowed to market the biosimilars in Europe and other parts of the world. They agreed to avoid the U.S. market until 2023. They also consented to pay royalties to AbbVie when they sold their drugs in the U.S. Watchdog groups thought the agreements were illegal and wanted the Federal Trade Commission to investigate.
At the 2019 Senate hearings, Gonzalez did his best to avoid discussing the biosimilar elephant in the room. He talked about his company’s failed attempt to develop a drug that cured hepatitis C and stated a willingness to work with the committee. He pointed out that his company is charitable and explained that it has 30,000 employees (and they need to eat). Senator Wyden, in turn, pointed out that Gonzalez’s salary was $22.6 million and he had recently received a bonus of $4.3 million.Wyden asked if the bonus was tied to the financial performance of Humira?
(At this point, if I were Gonzales, I’d say I didn’t write the law. As chief, I’m supposed to hire lawyers who will exploit the loopholes you guys allowed our lobbyists to put into the legislation. If you don’t like what’s happening, change the law.)
In September 2018, Congress passed John Sarbanes’ Biosimilars Competition Act. It is supposed to “shine a light” on backroom, so-called “pay-for-delay” deals that were often made in secret. They have to be reported to the Federal Trade Commission who, with the Justice Department, is supposed to review agreements, look for antitrust and anti-competitive behavior, and “punish bad actors.” In other words, if a company has a drug with annual revenues of $10 billion and they keep competitors off the market for five additional years, their company could bring in an additional $50 billion. Then the naughty owner has to notify the government, admit no wrong, and pay a fine of a few million dollars. Great law!!
Monoclonal antibodies
https://www.immunology.org/kohler-and-milsteins-hybridoma-technology-1975 https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(05)72025-0/fulltext
Cytokines –“Love and Science” by Jan Vilcek
BIOSIMILARS AND CYTOKINE BLOCKERS
Abbvie and biosimilars
Transgenic mice
https://www.ncbi.nlm.nih.gov/books/NBK231336/
toclizumab for overzealous release of toclizumab
https://www.thelancet.com/journals/lanrhe/article/PIIS2665-9913(20)30173-9/fulltext
Richard Gonzalez AbbVie
AbbVie and biosimilars
Pros and cons of 12 years exclusivity for biologics https://repository.library.northeastern.edu/files/neu:cj82rb53g/fulltext.pdf
European handling of biosimilars
In much of Europe biosimilars can be marketed as soon as they have been shown to perform as well as the original drug, but they are usually not thought of as interchangeable or a generic version of an existing medication. They are instead treated like a competitor or a therapeutic alternative, and outside of a small number of Eastern European countries pharmacists can’t substitute a biosimilar for a designated medication without permission from the prescribing physician. When the biosimilars begin to significantly price compete attitudes will probably change, but for now in France and Italy, at least, “biosimilar adoption rates have been low.”
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