Help needed comparing CTX & P1NP results

loriesco, the doubling P1NP is good, especially since you are following Reclast which would slow the advantage of Tymlos. I wanted to respond right away in case you are worried. More to say later.

loriesco,
you might find this https://www.youtube.com/watch?v=eqY7Bm9HiD0&list=PLRwK07HRBX0AacaOM-hn_Ut12jpdDYSUj&index=5 interesting. At26,30 in Bilezikian's presentation there is a chart reflecting the percentage rise from baseline for CTX and P1NP. We don't have your baseline before Reclast so we can't compare %ages. Ideally you'd have taken a P1NP one month in from starting Tymlos. At twelve months your P1NP would have lowered from the first month high. So we can't do comparisons (confidently). One year of Reclast would have lowered both CTX and P1NP from whatever your original base was.
I find it interesting that CTX has risen as much as it has within the year after Reclast.
I suspect that the doubling of the P1NP at twelve month is partially a reflection of the delayed PTH response after bisphosphonate. But that doubling has to be seen as good.
Thanks for posting your numbers. I'll be curious to see other responses to your post.

What if anything is too low a score for CTX? Endo ordered (after my request; have been on Fosamax for about 1 year, next step is Reclast per endo) both that and NTX blood tests. My CTX is 52; NTX 8.2, no discussion of P1NP. Dr. Google isn't helping much which I try to find information on CTX...NTX appears to be fine. Would love insight; only been on the annoying journey for a year!

jozer,
your CTX and NTX tell us that you aren't losing bone; Fosamax is working just as intended. I always like a measurement of P1NP because the value of loss and gain are dependent upon each other. P1NP is seldom measured with bisphosphonate use because it generally suppresses both. It is helpful to have markers before treatment and then one or two months after initial treatment.
Do you have numbers from dexa scans.
I'm linking a couple of video you might look at.

@loriesco, from what i understood, both P!NP and CTX undergo a serial change following dosing of Tymlos or Forteo. These changes are compared against their baseline values to show whether or not a therapeutic response (anabolic) is present.

A few ways to assess the anabolic response are written in various literature. A change in PINP more than 10mcg/L is often mentioned. Your lab value at 12mo Tymlos indicated a clear response. HOwever, this absolute change in value means very different for people with different baselines of P1NP (e.g., a low baseline of 35 vs a high baseline of 90) imo. Many clinical studies use % change from baseline. Your 108% change in P1NP from baseline also showed that you have an anabolic response.

What's not discussed clearly in literature is the impact of a higher CTX relative to P1NP on bmd improvements. Some of members here including me have/had high CTX during PTH-analog therapy. We will see how everyone's bmd fair at the conclusion of treatment. I had modest but satisfactory end results.

Generally speaking, in early months of Tymlos therapy, a significant increase in P1NP accompanied by a modest increase in CTX were seen in ACTIVE trial and other clinical studies. Your lab results at 12mo showed a slight larger % increase in P1NP over CTX. You might have missed the optimal lab "window" that showing higher P1NP response relative to CTX. With that said, it's hard to pick the right time for labs in your case since you had prior treatment with reclast, which complicates the whole picture, unless you labs were done every 3mo or so.

Hope you could get a dexa scan done after a year on Tymlos.

mayblin, thanks. From your perspective was the jump in CTX dramatic. Or, just so for me because of my own situation. What do you make of the stasis in %ages. Give us some speculation from your profound mind.

@gently and @mayblin THANK YOU! I am in receipt of your generous bounty of info! I started watching the youtube video Terry sent me this morning ( https://www.youtube.com/watch?v=eqY7Bm9HiD0&list=PLRwK07HRBX0AacaOM-hn_Ut12jpdDYSUj&index=5 ) and have a busy day with meetings, etc. but will respond (probably tomorrow). THANK YOU! The video is explaining everything... it was a lot to digest at 6 am on my stationary bike!

I want to say I was totally incorrect, this is no simple matter!!! Holy cow! Thank you everyone for the wealth of info.

Thank you gently! Sure wish docs would share info; got these tests and there has been no communication of what results may mean. Will check videos; I've looked at some of the (I believe) Dr. Doug ones; informative. L-spine gained 3%, L-hip 2% and no change in L femoral neck in the year of Fosamax (no right info, hip replaced 10 years ago). Have heard (doc google) that too low CTX can sometimes predict a higher risk of ONJ so maybe it's time for a new drug? Doc wants Reclast but I am still in the process of getting multiple second opinions (ortho, gyne, my IBS doc for handling stomach issues on bisphosphonates, and a rheumatologist). I have been wondering about the bone building drugs...

I am on TYMLOS for one year and I had RECLAST to start two years ago. I have IBS. So I am very careful when it comes to food and medicines. Unfortunately when I did the RECLAST, no one prepared me and I was only one month out from a double cervical spine surgery so it was probably not a good idea to do the RECLAST. I was one of the 10% who reacted to the drug unfavorably. I’ve had an experience like that before and so I chalked it up to needing the medicine. Sometimes when our system “fights“ something it’s with an immune system response and I had a severe reaction. It could’ve been controlled if I had known to drink the water and take Tylenol before I go in. As far as the TYMLOS I had the run-of-the-mill side effects the first two months. Again, I think it was my system reacting to needing the medicine.. From all the information I gathered “magically“ the side effects (being nauseous,, being fatigue, a little lightheaded, a little headache, achy, it all went away at two months. Also, someone here had recommended titrating up to the 80 units. So I started at 20 and once a week titrated up 10 units. we had conversation here about the belly and hip fat from Art injections. I’m not sure we could say it’s causal, but I think when you get good results, it confirms doing the medicine and overcoming the challenges. I grew up taking a ton of spills as my ankles were weak, and I was considered a klutz. So I just got used to picking myself up after I fell. Last year at age 68 I knew five women who fell and fractured or broke shoulders or hips in my circle. I’ll deal with the consequences of the medicine to get the improvement when they opened me up to do cervical surgery in 2023. My bone fell apart in their hands. I’ve taken DES every year for 25 years or more. Nothing prepared anyone for that. I’ll take the medicine.