CTX Marker

My humble understanding is that tymlos 'pushes - forces' the osteoblasts to build bone. After 16/18/22 months these cells do not respond as well to the medication. The osteoclasts are ramped up to 'dismantle bone' and this makes the 'bone coupling' ( 'building' compared to 'dismantling') out of sync.
Hopefully you have been keeping track of P1NP and CTX- bone markers. The 'bone building' rates can be checked thru bone makers ( P1NP ). When this result starts to wane compared to your history, then the medication is losing effectiveness. Tymlos is then stopped; a medication is given immediately for a short time to maintain the gains. Do not skip this step. I repeat do not skip this step. TYmlos was just apporved to be given again - how effective this is depends on many issues including bone markers and dexa and tbs. Make sure your endo is a BONE specialist. May you get good guidance and restore your bones to strenght and vitality.

After stopping Tymlos, what are the med choices to take afterwards? My endo said either Prolia or Reclast. But would Fosamax be an option? I'd prefer that vs an injection or infusion with the many side effects I've read about.

Wow. Thanks so much for this. My bone density tests showed a decrease after 6 years of no meds and my recent blood test showed a CTX 476 number which I couldn't interpret. The Dr who read the report wrote Normal - I ordered the test online and paid for it myself. My endocrinologist thought it useless.
She felt at my last visit that I shouldn't take Forteo again because of the black box label however I know that's been removed.
My only issue remains the same as it was 6 years ago after Forteo. I can't take Fosamax or Actenol and I refuse to take Prolia. This leaves Reclast and I've read horror stories of long-term effects.
My last bone density showed no change but my spine is -4.0.
I exercise and walk daily and am tempted to stay off meds altogether. Any advice?

CTx on it's own can be deceiving. For example, my January CTx was 115. After my third Evenity injection it went up to 355. If I hadn't had my P1NP to compare to, I would have thought that my treatment wasn't working. That couldn't be further from reality.
Comparison of the ratios of P1NP to CTx shows that my bone turnover improved dramatically. The P1NP went up so much, that it more than negated the increase in CTx.

When looking at these ratios and the following equation, you don't need to take into account that the unit of measurement given for CTx (pg/mL) is not the same as that for P1NP (ng/mL). When comparing ratios, that's not relevant.

Here are my scores and ratios for comparison:

Jan 2024
*P1NP=11*
*CTx=115*
The ratio was approximately 1 P1NP to 10 CTx.
This means that the CTx number was 10 times higher than the P1NP number.

April 2024
*P1NP=102*
*CTx=355*
The ratio was approximately 1 P1NP to 3.5 CTx.
This means that the CTx number was only 3.5 times higher than the P1NP number.

Another way to compare the two scores and track progress was covered in a YouTube video by Dr. Doug Lucas last December.
Here's the link: https://youtu.be/NgZf1Vu8UyM
This is the equation that he uses:
P1NP ÷ (CTx ÷ 1000) = X

When the answer (X) goes up, you're headed in the right direction.

Here are the numbers that I get when I do the calculation for my January and April tests:
January = 95.5
April = 287

Knowing the P1NP in my case makes a huge difference.

Hey, there, late to this conversation and wondering why you are hesitant to take Prolia? My sister had her first injection a couple of months ago and has been fine. I am hoping to finish my Forteo this year and Prolia was the recommended next step by 3 different doctors I met with, including the Chief of Osteoporosis and Metabolic Bone at the Hosp for Special Surgeries in NYC. He told me to begin Prolia once my Dexa shows -2.0, and get myself to 0 after which he recommends Reclast four months after the last Prolia injection, then 8 months later, another Reclast, and then another one 12 months later and then just monitor. Or, stay on Prolia for the rest of my life.
Honestly, I have heard horror stories about every single one of these meds but after the surprise of two fractured vertebrae (from a severe Covid cough 2 years ago) and shock of discovering I have osteo, I figure its better to do what I can. Forteo makes me tired and draggy, caused belly fat and weight gain and I've been on it now for 17 months and can't wait for it to be over.
Curious about your Prolia warning. Like you, I've been active, fit, etc although I'm still recovering from what began as a shin splint then turned into 10 months of marrow edema in my tibia --from 'overuse', they say. I'm not a tri-athlete, just a now 63 year old who has always been active. Sitting like a potted plant these last few months was a test of my sanity, but, I'm happy to say I graduated back to a boot today and just took a walk around the block...slowly. Anyway, thanks for listening to my woeful tale 🙂 and if you have no fractures, I'd be torn on taking anything but supplements myself. And walking, walking, walking every day.
best of luck!

You are young at 63. Prolia has its use in older patients who may need it for a lifetime. Prolia is very very difficult to get off of safely without traumatic fractures and its long term effect ( 20 yrs ) are unknown. I am not a scientist - but from all I have been told, it is dangerous drug.
Educate yourself as best you can - find out how to get off PRolia if you need to. YOu must be comfortable with the course of your treatment. Meanwhile Reclast is also very very strong...and has a long half life in the body. Do you need anything that strong???

I too have seen HSS in NYC - My doc at HSS would never give it to me at my age and I am 69. Now be aware HSS is research and evidence based - osteoporsis on the onther hand is a very individual case . In my opinion you need to be evaluated as an individual ( not how a 'group' of people responded) and find out the cause of your condition. Has HSS determined the cause ? HSS did a superficial job with labs - checked the basic VitD,PTH,wheat allergy phosphouse etc. THey did not test bone markers ( bone markers are critically important to moniter therapy) You have very complex issues going on and were very fit like me.
DId you have bone markers done? ( P1NP and CTX) I recommend a full lab evaluation with bone markers - check inflamamation, gi , and many other contributing factors. In my case there was no inflamation but high homocysteine, protein deficincny,high b6, high bilirubin and indications that there are genetic factors involved. - I had to work with an informed caring primary care and local docs. I have been disabled for almost 2 years and am determind to heal and teach and live again. I greatly recommend the book Great Bones by DR Keith McCOrmick - it is a bit scientific but stay with it and it will help your understand and guide your way.
Lastly if you have your bone marker history, your doc will have clear information about when to take you off FOrteo - some people come off 16 ot 18 moths, some can stay on it. Depends on bone markers - are you still building bone in relationship to the dismantling of bone??? There is no magic number to watch for; it is the porpostion of building/vs/ dismantiling based on your history. I myslef will recheck bone markers at 18 months of tymlos - if my building markers have pulmetted then I need to get off the medicance and onto something to help seal in the gains.
Sendign postive energy for you to find an caring and informed path to support and restore your health.

I just got my BTMs from earlier this month two weeks after my 6th Evenity injections. I'm comparing them to my BTMs done in April two weeks after my 3rd injections, and curious if there's anyone having their BTMs done every three months. My P1NP went up a bit, but my CTx went up a lot. I know that it's to be expected with Evenity that it's efficacy will wain over time, but, to be honest, my CTx score concerns me. If it's this high now, how much higher will it be in another 6 months?

April 2024
*P1NP=102*
*CTx=355*

July 2024
*P1NP=119*
*CTx=531*