Looking for cases of people using a second anabolic after the first

This may be helpful:
https://pmc.ncbi.nlm.nih.gov/articles/PMC11601723/.

@gravity3 thank you very much. I will take this study with me when I see my rheum.

cat1203, teriparatide and romosozumab work through entirely different mechanisms. Evenity may well work for you if Forteo hasn't.
I responded to suggest that you use bone markers to determine if the medication is effective, so that you don't spend a year on Evenity either uselessly or worrying. Having a serum P1NP before Evenity and a month in would let you know. Some like the second P1NP two months in but I'd be insistent not wanting a second injection without knowing. The jump in P1NP will be dramatic, even after successful use of Forteo.
Even further from your question (sorry), I think of Forteo, when is doesn't work,as a valuable hint that you may have secondary cause for osteoporosis which should be resolved before resuming medication, the main concern would be hyperparathyroidism.
I wonder from your post if you had some, but not enough gain from Forteo. I'd have quit Forteo after the first dexa if I didn't have bone markers telling me that this drug was doing some heavy lifting. Even after the second dexa when the only remarkable change was a change in fracture risk, I may have quit.
Forteo does something that Evenity can't. It rebuilds the cartilage structure in trabecular bone lost in the breakdown of bone. Cartilage isn't evidenced on dexa. I reasoned that Forteo is busy rebuilding cartilage, because I'd lost a whole lot before starting medication. I'm on extended Forteo.
You are on unchallengeable ground asking for bone markers after (wasting) 17 months without evidence of gain
I suspect you'll have good results on Evenity in no small part because of prior Forteo use.

@gently I had some gain from Forteo, but only in my spine, going from -3.8 to -3.5, a 4.6% increase. My left total hip and left femoral neck were unchanged, at -2.2 and -2.6, respectively.
My TBS score is 1.223, which is degraded microarchitecture, same as before.
My former rheum did not use BTMs to guide clinical treatment, which as I'm sure you know is not uncommon. I ordered and paid for them myself before starting on Forteo. CTX was 100; P1NP was 13. This was after 3.5 years on Fosamax.
Three months after starting Forteo, I had BTMs done again. CTX now 431 and P1NP 64. Since my rheum offered no interpretation, I relied on Dr. AI, which said "increased CTX is normal in the early stages of treatment with teriparatide. A higher CTX number after 3 months on teriparatide is expected because this medication primarily stimulates bone formation, which initially leads to a temporary increase in bone resorption (as measured by CTX) as the body starts the remodeling process to build new bone, even though the net effect is a gain in bone density over time; essentially, teriparatide "primes" the bone to rebuild itself by increasing bone turnover, resulting in a higher CTX level early in treatment. When monitoring P1NP levels while on Forteo (teriparatide), a significant increase of more than 10 µg/L from your baseline level after 3 months is generally considered a positive response, indicating that the medication is effectively stimulating new bone formation; this is often used as a benchmark to assess treatment efficacy. " So it seemed to me the Forteo was working.
I had no other BTMs and my DEXA on 3-12-26 was my first one since 3-11-24. (My very first DEXA on 10/27/2020 had my femoral necks at -2.3 and lumbar spine at -3.8, at which point I went on Fosamax. I might have quit Fosamax sooner had I had a DEXA two years later in 2022 but my PCP--I wasn't seeing a rheum at that time--never suggested it and I didn't know any better.)
I too wondered about underlying causes such as hyperparathyroidism for which I was tested prior to starting Forteo. Normal.
I am hopeful my new rheum, who I can't see until late May, uses bone markers and will agree with me about another, different round of anabolic, i.e. Evenity.

Cat1203, your bones responded well to Forteo.
Many lose density in the cortical bones of the hips as Forteo restores canaliculi- communication channels in the bone. Canaliculi collapse or filling is why all the osteoporosis medications except Forteo and Tymlos have cautions about the development of brittle bones.
Well done with the bone markers. If you had the last draw in the morning while fasting, the markers are indicating that it is time for a break from Forteo. Sequencing to Romosozumab (with cardiac clearance) should serve your bone density. You might consider that Romosozumab delivers the most bone density in the first three months, with the last six months being more antiresorptive.
You are way on top of the bone markers, so you probably already know that bone density isn't bone strength. Dexa measures density the the TBS software only measures density but looks at the homogeneity of loss. If the loss is concentrated in an area, that area is more likely to result in compression.
While the PTH drugs are working on reconnecting the collagenous network in trabecular bone, Prolia and Romosozumab are working on filling in the space between that trabecular bone, creating strength in density rather than in flexibility.
Have you thought about which medication might follow Romosozumab?

Eventiy can follow PTH meds - and there are studies to support this.
I took tymlos 22 months/ actonel six weeks/ and am now on evenity
My history is that I was fracturing ( non traumtic) both feet and discovered sever osteo and was put on tymlos.
There were a tremendous amount of tests done to clear up imbalances and eliminate disease possibilities including genetic work ups. PTH meds ( forteo more so but also tymlos) are known to reduce cortical strenght/quality in some people. Feet are primarily cortical bone ( as are forearm and hips also have a moderate amount of cortical . I stayed on tymlos 20 months but felt deterioation in the feet about month 18 but I didnt relaize it was the medicine. As tymlos was finished, I was put on Actonel temporairly until we figured out what to do for the feet. It was a bit of a battle. Evenity has a better response in cortical bone so that was the decision. I am now in my 11th month and the feet are improved. I will see dexa results in the next week.
Be a strogn advocate for yourself. This is a complex disease and every one has different circumstances Sending postive energy for your path to healing.

@dmshope

Great info. Thanks

@dmshope, I had read that microscopy indicates the increase in porosity in cortical bone with use of the pth drugs doesn't result in a loss of strength, but an increase in elasticity or bounce giving the bone a better opportunity to survive impact without fracturing. It seems to me that nowhere would that be more important than in the feet.
Experience is a better measure (for me) than abstract speculation. Anything more you can reveal about the deterioration in those feet of yours would be interesting for me. Were they imaged and/or aching. Was the discomfort after exercise or after sleep. Thanks, for this post, even if there aren't more answers answers.

I had MRI (showed weakend cortices and thinner after tymlos / weakend microarcheture also) and traditional CT on the feet- CT repeated one year after to assess diffrences. CT Imaging gave little info. I was told that a 'quatitative CT' would have bene better to do since it can measure the width of the cortices. I do not know if that is true - or where one can arrange a 'quantitative ct'.
Therefore my progress is based on personal symptom evaluation.; distance I can walk without needing to sit - how long I can stand ( more then 3 mins etc ) . It is also based on how 'crunchy' my feet feel - I realize that is not scientific but I can feel bones fatigue - thats my danger zone. I remain in heavily supportive footwear to reduce flex of feet bones. I have not fractured for 2 years.
Feet do not ache. They are alwasy better after rest . My Excereice is primarily lying floor work since I cannot stand for very long. I am Walking to one mile now which is a God send. I started at 25 ft.
I use a low intensity vibration platform to provide additional stimuation to bones; this took along time to acclimate to, due to nerve trauma becasue of the fractures. I didnt know that was a thing but my bones were so flet that they were compressing - like some people expereince in the spine- lA wodnerful DO helped me with thru that and the nerves settled down., thankfully Evenity has helaped me gain back some strenght in the feet , I am very thabkful, I have a Dexa soon and will chekc the other areas but honestly its my feet that Im concerned with. ( before med; Spine was -3.9 / hip -4/ forearm -4.7 / after tymplos spine -2.6 / hip -3.6 / forearm - 4.7)
WHere ever youare on your path I send postive prayers for your restoredhealing and strnght. This platform is very helpful and I am appriciative for the community support.

@cat1203

Your statement that you hope that your new rheum, who you cannot see until late May, uses bone markers.....raises an important issue that perhaps people here on Connect have found a way to respond.

Is there a way to find out whether a potential medical practitioner is open to and/or using blood markers before you go through the trouble AND the wait for an appointment?

I am looking for a bone specialist at present but I want to know ahead of any appointment that that provider is open to the use of bone markers. Not interested in wasting my time or theirs....was able to convince a previous primary care doctor to order CTX and (less often) P1NP. The cost of these tests is covered by my Medicare if there is a physician order.