Bone turnover markers (CTX and P1NP): do you have a baseline?

The CTX graph was a distribution pattern among untreated postmenopausal women with osteoporosis. Once a person starts an anabolic such as Tymlos or Forteo, both bone markers P1NP and CTX start dynamic changes. During the last few months of Tymlos treatment, both markers trend toward baseline. Publications indicated there are strong correlations between early changes (3-6 months) of bone markers and the subsequent bmd increase.

It's interesting that you had taken fosamax for 10 years in the past. Did you have a drug holiday before you started Tymlos?

I decided to stop taking Fosamax - no rhyme or reason. Then I had two fractures, wrist requiring a titanium plate and hairline palm. Did DEXA but not a substantial difference from the baseline. But family history on mother's side of back curvature and mother (lived to four months short of 100) experiencing old age fractures made me decide to consult Endo (w/PCP suggestion) to consider options to strengthen bones. I started Tymlos after basic bloodwork values (as well as 24 hours urine for specific markers), thyroid, Ca, Vit D, protein levels were normal.
In next few weeks (end of 2-yr Tymlos) and DEXA scan, I have to decide what's next. Thanks

Yes, infusions. Sorry for the confusion.

I have had osteoporosis for 8 years and have tried many drugs with 3 different doctors. My previous endocrinologist gave me Fosamax which caused jaw necrosis (I had taken for 2 years and needed dental work) and when that was discovered, she sent me to a specialist that deals only with osteoporosis. No one has ever given me a test for ctx or p1np and this is the first I have heard of that. I have been on forteo for 5 years now (yes, more than anyone else I suppose but I can't take the other drugs). Should I have been given a ctx or p1np ever? Do these test possibly have other names that I would recognize? Sounds like it is to late to get a base line.

Hi @magwil01 you are the first case that I've heard of getting Forteo for 5 years. Was is a continous 5 year treatment? Yes you missed baseline testing of bone markers. But the most important thing is Forteo helped you recover from jaw necrosis. If it is the only drug you could take, then testing bone markers from this point on may not be necessary because what can you or your doctor do without Forteo? Forteo is known to have a finite 'anabolic window'. Likely after 2 years it has much less effect in building more bones or increasing bone density. However, it may maintain bone mass if you stay on it; it is just very expensive.

P1NP: Procollagen Type 1 Intact N Terminal Propeptide
CTX: Collagen Type 1 C Telopeptide, or C Telopeptide

If you could, do you mind sharing your dexa results (in bmd% increase or T score) during the years that you are on Forteo? Or if you prefer, could you private message me please? I'm very interested in results from continuous Forteo therapy beyond 2 years as I'm at the end of 2-year Forteo. Thanks you very much!

I just switched doctors and was able to get for the FIRST TIME a CTX and P1NP. I do not currently take any Osteoporosis drugs, but have stabilized and improved my T-scores with lifestyle, diet, and exercise for the past 5 years. Here are the numbers:
CTX - 177
P1NP - 52 (which according to McCormick is high by 2 points)
I also got:
Vitamin D - 42
TSH - 3.67
Off to get out "Great Bones", and read what McCormick has to say about improving P1NP. Open to comments and advice.

Hi @mlwh your bone markers look great in that CTX was below the lower half of the range for healthy young women and p1np slightly above 50 percentile. How do you achieve that? Are you on anything special that we could adopt? It will be interesting to see how your bone density holds up with this bone marker reading. Please keep us posted with your next dexa. Thanks for sharing!

I will call to schedule a Dexa in October, (a year from my most recent, which I will have to pay for) but who knows how far out they will be booking. 🙂 I will post my results and see if they coordinate with my markers. I'm pretty pleased myself, so thanks for the kind support. I love the new doc, and she has restarted my transvaginal estradiol, which I had though may have been a part of my most dramatic Dexa improvements from three years ago. SO, maybe that is part of the magic sauce. Too soon to say, I think.

I just got my test results and I had an increase in P1NP. CTX has not been reported yet. Some background - I fractured my hip 11/23 I started tymlos on 5/24/24 titrating up and started full dose on 6/15.

5/9/24 - Baseline P1NP - 75
8/28/24 - P1NP - 162

Vitamin D dropped from 66.8 to 42.80
Calcium basically the same

Will report CTX when it comes in

Thanks and please let me know what you think.

This is fantastic @bluebonnet242 , a 116% increase in P1NP ~3 months into Tymlos! I am very happy for you!

A few members mentioned that VitD requirements went up during Tymlos or Forteo treatments. It won’t hurt to keep a close eye on its blood level. My intake of VitD was 4000iu per day and that kept my blood VitD level at ~50 pretty constantly.

Great news! Please keep everyone posted as your therapy progresses.