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HowtoHeightmaxx
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THIS IS NOT MEDICAL ADVISE
I tried to explain this topic as clearly as possible giving only relevant and important information, hope you enjoy.
What is Erdafitinib?
Erdafitinib is an oral inhibitor of FGFR1, FGFR2, FGFR3 and FGFR4. FGFR3 normally acts as an important brake on cartilage-cell activity inside an open growth plate. Blocking this pathway can therefore accelerate longitudinal bone growth very effectively.
Observed growth amount on erdafitinib
Documented responses vary yet users with open growth plates gained 9-15cms height in 6 months. However even though we saw significant changes in height published results do not provide a centimeters-per-milligram relationship . (there is a table at the bottom showing published documents about erdafitinib usage and results you can check it for yourself)
Erdafitinib main effects (Positives)
Established effects (supported by human evidence)
- Very quick linear bone growth
-Longitudinal bone growth independent of increased GH/IGF-1 activity
-Widening of growth plates
-Increased chondrocyte proliferation and activity
-Altered growth-plate architecture
Unestablished but Proposed effects (supported by theoretical evidence)
-Possible slower relative bone-age advancement (Case reports describe rapid linear growth occurring while skeletal maturation appeared to progress more slowly. This has been observed in a small number of patients but has not been proven in prospective studies.)
-Possible increase in bone-age delay (If bone maturation advances more slowly than chronological age while height continues increasing, the difference between bone age and chronological age could theoretically become larger.)
-Possible delayed growth-plate senescence or closure (Because growth plates appear wider and bone maturation may lag behind height growth in reported cases, it has been hypothesized that FGFR inhibition could delay growth-plate senescence or closure. However, no human study has yet demonstrated delayed closure or reopening of fused growth plates.)
Erdafitinib side effects (Negatives)
Note: Most frequency estimates below come from adult cancer patients receiving 8–9 mg/day in clinical trials. The exact risk at 3–5 mg/day or in healthy individuals is unknown but side effects are much more mild compared to cancer patients . Skeletal adverse effects are based mainly on pediatric case reports and small trials.
- Hyperphosphatemia (High blood phosphate) ~73%
- Nail disorders ~70%
- Diarrhea ~63%
- Mouth inflammation (Stomatitis) ~56%
- Elevated liver enzymes 47%
- Dry mouth ~39%
- Fatigue ~29%
- Reduced appetite ~27%
- Dry eyes ~25%
- Central Serous Retinopathy (CSR) / Retinal Pigment Epithelium Detachment ~22%
- Hair thinning / Alopecia ~25%
- SCFE Rare (frequency unknown)
- Epiphysiolysis Rare (frequency unknown)
- Bone fractures Rare (frequency unknown)
- Kyphoscoliosis Extremely rare (case reports only)
How to mitigate important side effects
We will not be aiming to reduce all side effects since there is a lot. I changed the color of the most important sides you could dnr the rest.
Hyperphosphatemia
Hyperphosphatemia causes the bones to become brittle and also leads to fractures and Kyphoscoliosis.
To mitigate it we can either use phosphate binders (Sevelamer carbonate, Calcium acetate, Lanthanum carbonate) or we can change our diet to a Low-phosphate diet where you basically don't eat high phosphate foods/drinks like: Cola, Processed meats, Processed cheese, Fast food, Nuts, Seeds, Bran cereals, Chocolate. Both are used in clinically btw so they will work.
Central Serous Retinopathy (CSR)
CSR is caused by FGFR inhibition. FGFR signaling helps maintain the retinal pigment epithelium. Sadly there is no clinically proven medication to fully clear this issue. Best way to mitigate this would be using saffron extract next to erda. However it is important to do CSR tests at home using a Amsler Grid. If your CSR is developing reducing the dosage is critical. Even after reducing you may see rapid CSR development in this case you should hop off for a week or two till your vision is fully healthy and hop on again.
How to use the Amsler Grid
Wear your normal reading glasses if you use them.
Hold the grid about 30–35 cm (12–14 inches) away.
Cover one eye.
Look only at the center dot.
Without moving your eye, ask yourself:
Are any lines wavy?
Are any squares stretched?
Are any areas blurry?
Are any areas missing or dark?
Repeat with the other eye.
If CSR develops
You might notice:
Straight lines becoming wavy (metamorphopsia)
A blurry patch
A gray or dark spot
Objects appearing smaller or larger than expected
SCFE/Epiphysiolysis
These sides are already pretty rare so you don't have to worry about them to much. To further reduce the chance of these the only thing we can do is reduce the weight going on to our legs in our daily lives this could be not hitting legs or losing weight if your obese.
Sources
pubmed.ncbi.nlm.nih.gov
pubmed.ncbi.nlm.nih.gov
pubmed.ncbi.nlm.nih.gov
pubmed.ncbi.nlm.nih.gov
pubmed.ncbi.nlm.nih.gov
pubmed.ncbi.nlm.nih.gov
pubmed.ncbi.nlm.nih.gov
https://pubmed.ncbi.nlm.nih.gov/42325002/
pmc.ncbi.nlm.nih.gov
pmc.ncbi.nlm.nih.gov
pmc.ncbi.nlm.nih.gov
www.frontiersin.org
clinicaltrials.gov
clinicaltrials.gov
dailymed.nlm.nih.gov
www.fda.gov
www.jnjmedicalconnect.com
I tried to explain this topic as clearly as possible giving only relevant and important information, hope you enjoy.
What is Erdafitinib?
Erdafitinib is an oral inhibitor of FGFR1, FGFR2, FGFR3 and FGFR4. FGFR3 normally acts as an important brake on cartilage-cell activity inside an open growth plate. Blocking this pathway can therefore accelerate longitudinal bone growth very effectively.
Observed growth amount on erdafitinib
Documented responses vary yet users with open growth plates gained 9-15cms height in 6 months. However even though we saw significant changes in height published results do not provide a centimeters-per-milligram relationship . (there is a table at the bottom showing published documents about erdafitinib usage and results you can check it for yourself)
Erdafitinib main effects (Positives)
Established effects (supported by human evidence)
- Very quick linear bone growth
-Longitudinal bone growth independent of increased GH/IGF-1 activity
-Widening of growth plates
-Increased chondrocyte proliferation and activity
-Altered growth-plate architecture
Unestablished but Proposed effects (supported by theoretical evidence)
-Possible slower relative bone-age advancement (Case reports describe rapid linear growth occurring while skeletal maturation appeared to progress more slowly. This has been observed in a small number of patients but has not been proven in prospective studies.)
-Possible increase in bone-age delay (If bone maturation advances more slowly than chronological age while height continues increasing, the difference between bone age and chronological age could theoretically become larger.)
-Possible delayed growth-plate senescence or closure (Because growth plates appear wider and bone maturation may lag behind height growth in reported cases, it has been hypothesized that FGFR inhibition could delay growth-plate senescence or closure. However, no human study has yet demonstrated delayed closure or reopening of fused growth plates.)
Erdafitinib side effects (Negatives)
Note: Most frequency estimates below come from adult cancer patients receiving 8–9 mg/day in clinical trials. The exact risk at 3–5 mg/day or in healthy individuals is unknown but side effects are much more mild compared to cancer patients . Skeletal adverse effects are based mainly on pediatric case reports and small trials.
- Hyperphosphatemia (High blood phosphate) ~73%
- Nail disorders ~70%
- Diarrhea ~63%
- Mouth inflammation (Stomatitis) ~56%
- Elevated liver enzymes 47%
- Dry mouth ~39%
- Fatigue ~29%
- Reduced appetite ~27%
- Dry eyes ~25%
- Central Serous Retinopathy (CSR) / Retinal Pigment Epithelium Detachment ~22%
- Hair thinning / Alopecia ~25%
- SCFE Rare (frequency unknown)
- Epiphysiolysis Rare (frequency unknown)
- Bone fractures Rare (frequency unknown)
- Kyphoscoliosis Extremely rare (case reports only)
How to mitigate important side effects
We will not be aiming to reduce all side effects since there is a lot. I changed the color of the most important sides you could dnr the rest.
Hyperphosphatemia
Hyperphosphatemia causes the bones to become brittle and also leads to fractures and Kyphoscoliosis.
To mitigate it we can either use phosphate binders (Sevelamer carbonate, Calcium acetate, Lanthanum carbonate) or we can change our diet to a Low-phosphate diet where you basically don't eat high phosphate foods/drinks like: Cola, Processed meats, Processed cheese, Fast food, Nuts, Seeds, Bran cereals, Chocolate. Both are used in clinically btw so they will work.
Central Serous Retinopathy (CSR)
CSR is caused by FGFR inhibition. FGFR signaling helps maintain the retinal pigment epithelium. Sadly there is no clinically proven medication to fully clear this issue. Best way to mitigate this would be using saffron extract next to erda. However it is important to do CSR tests at home using a Amsler Grid. If your CSR is developing reducing the dosage is critical. Even after reducing you may see rapid CSR development in this case you should hop off for a week or two till your vision is fully healthy and hop on again.
How to use the Amsler Grid
Wear your normal reading glasses if you use them.
Hold the grid about 30–35 cm (12–14 inches) away.
Cover one eye.
Look only at the center dot.
Without moving your eye, ask yourself:
Are any lines wavy?
Are any squares stretched?
Are any areas blurry?
Are any areas missing or dark?
Repeat with the other eye.
If CSR develops
You might notice:
Straight lines becoming wavy (metamorphopsia)
A blurry patch
A gray or dark spot
Objects appearing smaller or larger than expected
SCFE/Epiphysiolysis
These sides are already pretty rare so you don't have to worry about them to much. To further reduce the chance of these the only thing we can do is reduce the weight going on to our legs in our daily lives this could be not hitting legs or losing weight if your obese.
Sources
Discovery and Pharmacological Characterization of JNJ-42756493 (Erdafitinib), a Functionally Selective Small-Molecule FGFR Family Inhibitor - PubMed
Fibroblast growth factor (FGF) signaling plays critical roles in key biological processes ranging from embryogenesis to wound healing and has strong links to several hallmarks of cancer. Genetic alterations in FGF receptor (<i>FGFR</i>) family members are associated with increased tumor growth...
Erdafitinib to treat urothelial carcinoma - PubMed
Erdafitinib is the first Food and Drug Administration (FDA)-approved oral pan-fibroblast growth factor receptor (FGFR) kinase inhibitor that binds to four FGFRs (FGFR-1 to -4), leading to decreased cell signaling and cellular apoptosis. Erdafitinib also binds to RET, colony-stimulating factor 1...
Population Pharmacokinetics of Total and Free Erdafitinib in Adult Healthy Volunteers and Cancer Patients: Analysis of Phase 1 and Phase 2 Studies - PubMed
A population pharmacokinetic (PK) model was developed using data pooled from 6 clinical studies (3 in healthy volunteers and 3 in cancer patients) to characterize total and free plasma concentrations of erdafitinib following single- and multiple-dose administration, to understand clinically...
Prediction of the drug-drug interaction potential of the α1-acid glycoprotein bound, CYP3A4/CYP2C9 metabolized oncology drug, erdafitinib - PubMed
Erdafitinib is a potent oral pan-fibroblast growth factor receptor inhibitor being developed as oncology drug for patients with alterations in the fibroblast growth factor receptor pathway. Erdafitinib binds preferentially to α1-acid glycoprotein (AGP) and is primarily metabolized by cytochrome...
Erdafitinib for locally advanced or metastatic urothelial carcinoma - PubMed
Erdafitinib for locally advanced or metastatic urothelial carcinoma
Erdafitinib in patients with advanced solid tumours with FGFR alterations (RAGNAR): an international, single-arm, phase 2 study - PubMed
Janssen Research & Development.
Accelerated Linear Growth during Erdafitinib Treatment: An FGFR-Related, but Growth Factor and Sex Steroid-Independent Mechanism? - PubMed
While targeted therapies including TKIs have become an essential part of adult cancer treatment, applications in children are still limited. Off-target effects specific to the pediatric population have been observed in various organ systems; however, knowledge about the effect of TKIs on the...
Skeletal overgrowth in a pre-pubescent child treated with pan-FGFR inhibitor - PMC
Fibroblast growth factors and their receptors (FGFR) have major roles in both human growth and oncogenesis. In adults, therapeutic FGFR inhibitors have been successful against tumors that carry somatic FGFR mutations. In pediatric patients, trials ...
Tumour-agnostic efficacy and safety of erdafitinib in patients with advanced solid tumours with prespecified FGFR alterations: RAGNAR phase 2 study primary analysis - PMC
FGFR alterations (alt) are reported across various malignancies and may act as oncogenic drivers in multiple histologies. Erdafitinib is an oral, selective pan-FGFR tyrosine kinase inhibitor with activity in FGFR-altered advanced urothelial ...
Erdafitinib in Asian patients with advanced solid tumors: an open-label, single-arm, phase IIa trial - PMC
FGFR genomic aberrations occur in approximately 5–10% of human cancers. Erdafitinib has previously demonstrated efficacy and safety in FGFR-altered advanced solid tumors, such as gliomas, thoracic, gastrointestinal, gynecological, and other rare ...
Frontiers | Case report: Slipped capital femoral epiphysis: a rare adverse event associated with FGFR tyrosine kinase inhibitor therapy in a child
We report a case of Slipped Capital Femoral Epiphysis (SCFE), an on target skeletal toxicity of a pan-FGFR TKI inhibitor, erdafitinib. A 13-year-old boy was ...
ClinicalTrials.gov
ClinicalTrials.gov
DailyMed - BALVERSA- erdafitinib tablet, film coated
FDA approves erdafitinib for urothelial carcinoma
On January 19, 2024, the Food and Drug Administration approved erdafitinib (Balversa, Janssen Biotech) for locally advanced or metastatic urothelial carcinoma.
Use of BALVERSA in Pediatric Patients
A summary of clinical data regarding BALVERSA® (erdafitinib) use in pediatric patients