Hepatitis C Lingo: What is a Log?

Okay, you are going into treatment.  You must understand the language of treatment progress. No one values your health more than you.

Getting information off the Internet is like taking a drink from a fire hydrant.   Mitchell Kapor

 Treatment response is a topic of great importance to me, you, and doctors.  They need  to see if the treatment is working enough to keep poisoning you.

Viral load is how to measure response. It’s done  by looking at the amount of virus in your blood. Viral load is checked before treatment,  at week 4, 12, and either 24 or 48, depending on duration of therapy, then 24 weeks (6 months) after therapy.   The response is measured in log reduction.    In fact log stands for logarithmic.  So what?  Each log corresponds to a factor of 10.  So what?  A 1-log reduction means virus decreases by 10 times; a 2-log = 100, a 3-log = 1,000, a    6-log reduction = 1,000,000 = 1 million.  Log is a way of not writing down all the zeros.  Just count the zeros gone and you get the number of viruses that died per ml of blood and went away.  Sort of.  There, in one paragraph we discussed a concept that took me some time to learn.  And you thought you would never use that math junk.

When I was in middle and high school, I had it in my head that my brain wasn’t “smart enough” for math and chemistry, even though I skipped kindergarten and the 2nd half of my senior year.   So I avoided the hard sciences.  Remember I was still GOD, grown up on duty, at my house. Then in my 20s, I went to college and I decided I didn’t want to fear math and chemistry any more. I took inorganic chemistry with algebra on the side to understand the language of thermodynamics.  This is an example of how my childhood perceptions always played down my abilities even though my family said I was smart (which I loved but didn’t believe) . I graduated from pharmacy school at 30,  then went back for a Dr. of Pharmacy in my 50s (while traveling around the country for work and, unaware that Hep C was dragging me down).

Why am I interjecting these little stories in the middle of scientific drama?  Because there is no scientific drama!

All measures must have units:  pounds of pressure per square inch (PSI), miles per gallon (MPG), ears of corn per stalk (one).  Notice the word per in each. The  Hepatitis C virus (HCV) is number of copies of the virus per ml of blood. The hepatitis C virus, like all viruses, cannot reproduce by itself. It must first infect a living cell, such as the hepatocyte, and take over the cell’s “machinery.” Using the genetic information in your cell, the hepatitis C virus is able to make copies of itself which can go on to make more copies.  The virus is measured in copies per ml of blood.  I know, weird.

Lindenbach B, Rice C (2005). “Unravelling hepatitis C virus replication from genome to function”. Nature 436

BTW, kids in Middle School know this stuff.  Amazing.    We will talk about RNA another time.  I know you can hardly wait.

Source:  Vertex website, Wikipedia

http://www.vrtx.com/assets/pdfs/VRTXHCVTreatmentResponse.pdf

www.wikipedia.com

and my brain: no link

Partial Responders with Hepatitis C

All Hepatitis C studies are not created equal. Duh

I used to see myself as smarter than the average bear.  Not so much now.

Being me, I was not passive when searching for a Hep C study.  But I was mistaken.   I assumed. Don’t make an assumption.  I knew better.   My mom taught me this.  Every time some of us kids got in trouble, she pulled me aside and said, “You know better”.  It was years before it dawned on me that other kids knew better too.  My mom was once a kid.  In fact she was still a kid when she had me.  In 1951 it was not cool to have a baby out-of-wedlock.  My biological father passed on marriage and she had to go back home to Harlan County, Ky.   This is where I was born.  Papaw told me to say I was from “Bloody Harlan” because of the bloody mine strikes.   So that is what I told my teacher.  Papaw and all Moms’ brothers were coal miners.  We didn’t make moonshine (the other career path)

I learned that the TV show Justified   is about Harlan County.  I don’t watch it myself.  Makes me jumpy.

fig 1.Me, Mom in the white car coat, dad that raised me, Mamaw, Papaw, and aunts. Harlan County, KY. My mom has the big nose like Papaw.  She waited to get a nose job after Papaw died

Coal tipple loads rail road cars 1

When I was a curly headed baby
My daddy sat me down upon his knee
He said, “Boy, you go to school and learn your letters
Don’t you be a dirty miner like me”

I used to think my daddy was a black man
With script enough to buy the company store
Now he goes downtown with empty pockets
And his face is white as a February snow

I was born and raised in the mouth of the Hazard Hollow
Coal cars rambled past my door
Now they’re standin’ in a rusty row all empty
And the L & N
Don’t stop here anymore

http://www.sing365.com/music/lyric.nsf/The-L-amp-N-Don’t-Stop-Here-Anymore-lyrics-Johnny-Cash/6B378501111ECA5D48256DEA000A5308

I love this song but never heard it until I moved to Texas

Where was I?    Okay brain get back on track.  Let me recommend that you do not have your driver’s license photo taken while on treatment. Very scary.

I chose to participate in a Multi Centered, Randomized, Placebo Controlled, Double Blinded study, evaluating Standard of Care (SOC) Interferon and Ribavirin (which had been my only choice all these years) vs. SOC and telaprevir for round one.  In fact I sought out this study. There were three arms, two with study drug.  I had a 66.7% chance of receiving study drug.  As I learned later, I was not randomized to study drug (telaprevir).  I assumed SOC included addressing anemia and other life threatening events.  In this case, SOC did not include blood transfusions or red blood cell (RBC) stimulant injections such as Procrit.  Standards of care have not caught up to current practices. Step one was to reduce the Ribavirin dose.  .  My hemoglobin (HgB) was 8.9 and the guideline minimum for taking Ribavirin is 10.0. Normal HgB range for females is 11.5-15.8 mg/dL.   My Ribavirin dose was decreased. Hemoglobin got slightly better but I paid for it later by not clearing the virus. In order to treat the anemia I would have to walk away from the study.  Dang it!   I quickly lost the ability to walk down a hallway, climb stairs or lift baggage without major shortness of breath (SOB) and the ability to complete a thought, all necessary for my job (oops, career). More about that later.

After treatment completion, an individual is assessed for response to measure viral load. If there is virus remaining but a reduction of disease by 30% or more  – it is called a partial response.   Partial response (PR) implies further treatment  required.  www.about.com   I moved from treatment naïve to partial responder.  Here I had saved myself for newer treatments but still got the same treatment that was available years ago.  Plus no treatment for the anemia.  How did a smart girl like me get in a dumb box like this?  I hung in there and finished the (long) 48 week trial.  Not only did I not have red blood cells (RBCs) or white blood cells (WBCs), but then the virus that was left was a stronger warrior.   Not good.  Here is the part where my education went out the window.  I was so depressed that I couldn’t function.  Every little thing was monumental.  I should have quit the study when my blood chemistry went to hell.  But I couldn’t think clearly enough to look at the situation logically.  All my decisions were made by a scared little girl.  See fig 1

You know I wanted to blame insurance companies.  It is so easy to blame insurance companies.  I wanted to blame pharmaceutical companies and the FDA.  They are easy targets too.  In reality, I, more than most, understand the study requirements and commitments. Sort of. I have been a research pharmacist for a couple of decades.  The data must be unsullied from outside forces like blood transfusions that will make it impossible to evaluate the toxicity.  That is the point of the study, not patient care.  Don’t misunderstand me.  Patients are well cared for. A patient can get treated without a study but a study cannot evaluate a treatment without patients

FYI, HgB is the molecule in the blood that carries oxygen, (O2) from your lungs to your blood and carbon dioxide (CO2) to your lungs so you can exhale this gas.  Speaking of HgB, it is a bucket brigade that carries water to a fire.  Even if you have plenty of water, if you don’t have enough buckets, the barn burns down.  Wait, that wasn’t a great example.  It wasn’t completely accurate either.  Never mind.  It’s just that I spent all these years learning this stuff; I want to get my money’s worth.  Kurt Vonnegut said only hermaphrodites use a semi colon; .Sort of.  While metaphorically I don’t relate to that, he did say it.   I didn’t pay Kurt Vonnegut, God rest your soul Mr. Rosewater.  Anyway my WORD grammar check said uses it.  I think I paid for that.  Yes of course I did.

Telaprevir (Incivek) and boceprevir (Victrelis) are now available to add to Standard of Care (SOC).  In fact by now they may be a part of SOC.  Glad I contributed to the body of knowledge that is clinical research.  Really I am.  But I wouldn’t repeat round one for nothing, not no way, not no how. It was two years before I was well enough to go for round two of treatment.  My career never recovered.