Laurie Kelley

Factor Products: Purity vs. Safety

Laurie Kelley May 9, 2021

Parents and patients often wonder about the safety of their factor product. Our community suffered terrible losses from contamination of the nation’s blood supply in the 1970s and 80s, so safety is paramount for us. But we often confuse purity and safety when describing factor concentrates. Purity and safety often go hand-in-hand, but in a medical context they have very specific meanings.

Purity: a measure of the presence of other proteins, sometimes including other clotting factors, in addition to the specific factor supplied in the concentrate

Safety: the removal or inactivation of potentially harmful substances, including blood-borne viruses, from factor concentrate

So purity refers to how much of your factor concentrate contains just factor, with no other proteins. Safety refers to reducing the risk of viral transmission.

Purity is measured by specific activity, the ratio of the desired clotting factor protein to the total protein in the concentrate, minus any added albumin (a blood plasma protein).

How is factor purified? That is, how are extraneous proteins removed from factor? By a manufacturing process called chromatography. In simple terms, chromatography involves passing a mixture containing factor through a column (like a glass tube). The column normally contains small beads coated with a substance that attracts the factor and removes it from the mixture. The column is then flushed out to release the factor, resulting in a final mixture that is thousands of times higher in purity and more concentrated than the original mixture.

Please don’t be misled by the term intermediate! These products are still of high purity, although not as high as the ultrapure or monoclonal ones. And note that the various purity levels do not mean there is any less quality control or consistency in manufacturing. Recombinant products are not produced from human blood plasma. They are produced in large stainless steel tanks, called bioreactors, which contain trillions of cells. Into each of these cells, a gene for human factor has been inserted, or “recombined”—the origin of the name recombinant. These genes produce human factor and release it into the culture medium—a nutritious liquid that keeps the

animal (or host) cells alive and growing. Although the source material is not blood, some recombinant products contain extraneous human or animal proteins introduced during the production process or added to the final product.

Next week: What do different generations mean?

Excerpted from Raising a Child with Hemophilia by Laureen A. Kelley.

Types of Factor Concentrate

Laurie Kelley May 2, 2021

Last week we shared new about Sevenfact, a commercial blood clotting recombinant product made from transgenic rabbits. But that made me think: maybe we should step back and review what types of factor products there are to begin with.

There are different kinds of factor concentrates, all with distinct brand names and made by different companies, but all blood-clotting factor concentrates are classified as one of two types:

• Plasma derived • Recombinant

The major difference between the two types is the origin of the factor, called the source material.

• Plasma-derived factor originates from human blood plasma.

Recombinant factor originates from genetically engineered mammalian cells containing the human gene for factor (not from human blood).

You might think that recombinant products have an advantage because they don’t come from human blood, but some still contain extraneous (unwanted) proteins—human and even animal. To understand the differences among products, you first need to know how various factor products are manufactured.

Plasma-derived factor concentrates are categorized by their degree of purity. Recombinant factor concentrates are categorized by how they are produced. Different—although very similar—manufacturing processes can create products with slight molecular differences in the factor protein and with varying degrees of extraneous proteins in the final product. Here are classifications of factor products, based on varying degrees of purity or differing manufacturing processes:

Plasma derived

• intermediate purity • high purity • ultrapure (monoclonal)

Recombinant

• first generation • second generation • third generation • fourth generation

Several recombinant factor products also have a prolonged half-life, allowing you to infuse less frequently. The first of these new products was introduced in 2014.

Why are there so many kinds of manufacturing processes? Why not just use one method to produce factor? In some cases, it’s partly a legal matter: if manufacturer A creates an effective way to produce factor, then A usually patents the process. No one else can use it. Manufacturer B will need to find another way! So manufacturers have developed a variety of slightly differing processes to produce factor.

It’s also a matter of purity and safety. Different products use differing source material and require specific types of manufacturing methods to ensure safety. Due to varying production methods and the type of factor, the relative purity of the final products varies. Purity and safety are two terms you must understand to know which brand of factor to choose, because not all factor concentrates are created equal.

Do you know the difference between purity and safety? It’s easy to confuse them. We’ll review them next week!

Excerpted from Raising a Child with Hemophilia, Laureen A. Kelley 2016

Factor from Rabbits?

Laurie Kelley April 25, 2021

Paul Clement

Factor from rabbits you say? Yes! On April 1, 2020, The Food and Drug Administration (FDA) granted approval of a new recombinant factor VII (FVII) product—Sevenfact—to France-based LFB Biotechnologies Group.¹ In the US and Canada, Sevenfact is sold exclusively by HEMA Biologics, a Louisville, KY-based biopharmaceutical company.

Until now, all recombinant factor concentrates were produced by inserting a gene for a human clotting factor into mammal cells, which then gives the cells the ability to make human factor. These “transgenic” cells, such as BHK cells (baby hamster kidney); CHO cells (Chinese hamster ovary); or more recently, HEK-293 cells (human embryonic kidney), are then grown to great numbers in large stainless-steel tanks called bioreactors. As the cells grow in the liquid culture medium in the bioreactor, they secret factor into the liquid, some of which is periodically drawn off, purified, concentrated and eventually processed into clotting factor concentrate.

Enter Sevenfact.² The production of Sevenfact does not involve the use of cell lines and bioreactors, but instead involves rabbits. The rabbits are genetically engineered—given a copy of the human gene for FVII that is designed to be expressed in the mammary gland and secreted into the rabbit’s milk. During the separation and purification process of the FVII, the factor is activated, producing activated FVII, or FVIIa.

Why rabbits? Clotting factors are complex proteins. And although genetically engineering a cell by adding a gene for human factor may confer it with the ability to produce human factor, the factor is not fully functional until it is “finished” or modified by the addition of different compounds and folded into a specific shape. This modification process is largely dependent on the type of cell making the factor and most animal cells are not capable of properly finishing human factor proteins. Rabbits do the best job of making factor very close to how humans make factor. In other words, rabbits produce very “human like” factor, which may also have an added benefit of decreasing immunogenicity (the likelihood of producing inhibitors). Rabbits have several other advantages as well: they are small, reproduce rapidly and their milk has a high protein content, meaning they produce more factor than other animals when comparing the same volume of milk.

Producing factor in bioreactors is a rather inefficient process. Rabbits do this much more efficiently and at a much low cost—they do not require large, expensive, highly complex facilities to house bioreactors, and unlike conventional facilities that take years to plan and build, production can be rapidly scaled up. Rabbits can produce 200 milliliters of milk per day, or nearly 7 ounces, and they lactate for about three weeks. A single rabbit can produce about 1 to 1.5 liters of factor-rich milk per lactation period, for a yield of 10–15 liters of milk per year. And they do not have seasonal reproductive cycles that would limit milk production as do many other animals.

Sevenfact is very similar to another recombinant FVIIa product on the market called NovoSeven RT (Novo Nordisk). Sevenfact is a bypassing agent, meaning it’s indicated for the treatment and control of bleeding episodes occurring in adults and adolescents 12 years of age and older with hemophilia A or B with inhibitors (neutralizing antibodies to FVIII or FIX).

In addition to FVIIa, there is also another bypassing agent on the market for people with hemophilia A or B with inhibitors: FEIBA (Takeda), which is a plasma-derived activated prothrombin complex concentrate (aPCC). And in 2017 the FDA approved a novel antibody therapy called Hemlibra, which can be used for prophylaxis in people hemophilia A, with and without inhibitors (it’s not used to treat bleeds).³

Hemlibra has revolutionized the treatment of hemophilia A with inhibitors because it dramatically reduces the frequency of bleeds—but people may still have breakthrough bleeds, requiring the use of a bypassing agent. In clinical trials of Hemlibra, patients who used FEIBA at doses greater than 100 U/kg/24 hours sometimes developed unwanted blood clots, but no such adverse event was found in patients on Hemlibra treating bleeds with rFVIIa. Because of this concern, many patients on Hemlibra prophylaxis instead prefer a rFVIIa, such as SevenFact. LFB has conducted laboratory tests of Hemlibra and SevenFact, and is currently enrolling patients on Hemlibra in a clinical trial using SevenFact to treat breakthrough bleeds.⁴

For more information on Sevenfact, visit the HEMA Biologics website at: https://hemabio.com/

This is an original article with no corporate sponsor input or funding.

1. LFB Biotechnologies Group: Laboratoire Francais du Fractionnement et des Biotechnologies 2. Coagulation FVIIa [recombinant]-jncw or eptacog beta). 3. (emicizumab-kxwh [Hoffman‐La Roche]) 4. https://onlinelibrary.wiley.com/doi/full/10.1111/hae.14253

Wearing White for Hemophilia

Laurie Kelley April 17, 2021

World Hemophilia Day, April 17, is when our community typically wears red, to signify blood, and our unity by blood. I decided years ago to wear white. Why white?

The widely used hemophilia logo features a red and white person standing together in unity. The red represents those with access to factor; the white, those without. And that’s why I wear white. To represent the people I serve most, in developing countries where little to no factor exists, or where donations of factor are not a consistent or sure thing. The logo used to feature a white feature leaning on a red figure, but this was eventually deemed disempowering. I agree!

Around the world, the hemophilia community is encouraged to speak out about hemophilia, to educate the public and to celebrate achievements on this day. Here’s an impressive video of youth in the Philippines; please watch! I visited the Philippines in 2008, when very little was being done to make substantial change. It is now happening, with even a Filipino senator getting involved with World Hemophilia Day! #PassHemophiliaBillNow

https://tinyurl.com/WHD2021YouthVideo

And this Facebook posting was written by a once little boy I met in Pakistan, who is grown now, and has suffered but overcome so much. I’ve been to his home; his family is poor. But he has a future and attitude is everything. Read this amazing post:

Accept Yourself

This day is not to highlight your deficiencies, not to remind you about what you are deprived of.
The day is to Celebrate,
Celebrate we were, we are and we will together like a family.
Celebrate that someone is always there to bring you all the way back towards normal life.
The day is to give gratitude,
To all those who put their efforts from minor to major to make our lives less-miserable, either they themselves are haemophiliac or not.
To all those parents that were and are facing from social stigmas and taboos but they are still with us with more power than before.
Thank to yourself that you still believe in you, becoming stronger and having consistency each day.

Last but not the least, we are all come up with our long struggle stories full of difficulties but what matter is that we are still standing all the way with positivity that God who has created us, has planned something more better than this.
Imperfections makes you beautiful, unique from others. So, to All Out There, You Are Not Alone!
If the glass is half empty, look at that it is half full, too.
This is how life goes on…
ACCEPT YOURSELF!

By M Zubair Ghafoor

Happy World Hemophilia Day and let’s keep on, in the memory of those we have lost, for those still living and in need, and for those not yet born.

Why Harry Doesn’t Have Hemophilia

Laurie Kelley April 11, 2021

The randy royal Harry has been usurping the news lately, after his infamous interview with Megan on Oprah. But the royal who truly deserves some attention is Prince Phillip, Queen Elizabeth II’s spouse, who died last week at age 99. Hemophilia is known as the “royal disease,” primarily due to Phillip’s and Elizabeth’s joint family tree: Phillip’s great-great-grandmother was Queen Victoria, a known carrier of factor IX deficiency, also called hemophilia B. Let’s look at his family tree, to answer the question, why doesn’t Harry (or William, or Charles, or Phillip) have hemophilia?

Prince Phillip was born a prince (unlike Diana, Camilla, Kate and Megan, who married into the family). His mother, Princess Alice, was a great-granddaughter of Queen Victoria. Phillip was descended from the third child of Queen Victoria, also called Alice, who like her mother, was a carrier for factor IX deficiency, or hemophilia B. In fact Queen Victoria had nine children, of whom two were carriers (Alice and Beatrice) and one had hemophilia (Leopold). These are very good odds!

Alice married Louis IV, the Grand Duke of Hesse. Alice introduced hemophilia into the House of Hesse and this German lineage. There were 7 Hesse children, and like their grandmum, one had hemophilia (Frederick) and two were carriers (Victoria, Phillip’s grandmother, and Alix). Alix married the Tsar of Russia, Nicholas II, and gave birth to Alexis, who had hemophilia. So, Prince Phillip has a long and illustrious side to his family tree regarding hemophilia! It’s been proposed that Nicholas II was so distracted by his son’s suffering due to hemophilia, that eventually he lost his grip on the monarchy at a time when the Bolshevik Revolution was poised to strike. And it did.

Queen Elizabeth? Not so much drama with hemophilia. Why? She is not a carrier of hemophilia. She is a direct descendant of King Edward VII, a son of Queen Victoria who did not have hemophilia. Now, Queen Elizabeth and Prince Phillip are related as third cousins. But since Phillip did not inherit hemophilia from his mother (not a carrier) or grandmother (also not a carrier but with a flip of the genetic coin might have been), and since Queen Elizabeth had no hemophilia in her direct line, neither Charles nor his sons, William and Harry, have hemophilia.

Harry’s got other problems, but hemophilia isn’t one of them, thankfully!