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MyDeficiencies

Palopegteriparatide

parathyroid hormone replacement, TransCon PTH(1-34) prodrug

Also sold as Yorvipath.

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Findings for this medication

Research about this medication, graded for how strongly each finding can be attributed to it. Nothing here describes your own levels.

Palopegteriparatide is a genuinely different case from the anabolic PTH(1-34)/PTH(1-34)-analog drugs already reviewed in this project (teriparatide, abaloparatide). Those drugs are given to people whose calcium and PTH axis are otherwise normal, so any calcium rise is an unwanted, excess-direction side effect. Palopegteriparatide is given specifically because the patient's own parathyroid hormone is absent or insufficient, so the drug's core job is to raise low calcium and lower high phosphate toward normal, not to push a normal system higher. That makes the calcium finding here bidirectional rather than one-directional: the regulatory label and two independent Tier A trial publications document frequent, dose-related hypercalcemia (54.1% of treated subjects with albumin-corrected calcium above 10.6 mg/dL at some point, 13.1% above 12 mg/dL, 8% symptomatic, one reported overdose-related hospitalization at 16.1 mg/dL), graded red, while the same label documents a separate, serious hypocalcemia risk, highest with abrupt discontinuation or a missed dose of three or more days, that is not a depletion effect but the direct, expected consequence of withdrawing replacement therapy from a patient with no functioning parathyroid reserve. Phosphate and the vitamin D axis move in the direction of correction, not depletion: serum phosphate falls from a baseline that runs at the high end of normal (4.2 mg/dL) to mid-normal (3.7-3.8 mg/dL) by week 26-52 without reported hypophosphatemia, and by week 52 essentially all trial participants (95-100%) had discontuinued exogenous active vitamin D entirely while maintaining normal active 1,25-dihydroxyvitamin D, because the drug's stimulation of renal 1-alpha-hydroxylase now supplies it endogenously. Both are graded orange. Magnesium, despite a plausible shared renal-handling mechanism and a real, well-documented magnesium-wasting signal for the class relative, teriparatide, showed no decline in palopegteriparatide's own pivotal-trial data (stable at 2.1-2.2 mg/dL through 52 weeks); this is graded yellow specifically to carry that reassuring null result forward rather than dropping it.

parathyroid hormone replacement, TransCon PTH(1-34) prodrug · ATC H05AA05 · also sold as Yorvipath · reviewed 2026-09-29. This describes research about the medication. It does not say anything about your own levels or health.

How to read the evidence grades

These colours describe how strongly a finding can be attributed to the medication in the research. They are not a severity score and they say nothing about your own health.

Grades describe how strongly a finding can be attributed to Palopegteriparatide in the research — not how common it is, how serious it would be, and not anything about you personally.

Red — Severe
Two or more independent Tier A sources, this drug in the cohort, the nutrient directly measured, consistent direction, clinically meaningful magnitude, a named mechanism, no substantial contradicting Tier A evidence.
Orange — Moderate
At least one Tier A source with this drug in the cohort showing a real but bounded deficit: an exposure window, a subgroup, low frequency, or a functional rather than circulating deficit.
Yellow — Low
Mechanistic plausibility only (Tier B), or class extrapolation (Tier C) with no drug-specific human status data; also used for context flags and interactions running the other direction.
Not graded — disclosed evidence gap
Nothing has been measured here, so this finding cannot be graded. That does not establish either safety or harm, and it is not the same as a White result.Source definition: Not gradeable under the rules above because nothing has been measured. Published as a documented gap, never as reassurance that there is no effect.

What the research found

Calcium, frequent dose-related hypercalcemia on one side, serious discontinuation hypocalcemia on the other

Red — Severe

See study details

Palopegteriparatide reliably shifts serum calcium in both directions depending on dosing state: hypercalcemia is common and well quantified during treatment, especially early, while serious hypocalcemia is the defining risk if replacement is interrupted or withdrawn abruptly.

Full detail and limits

What the grade means here: Two or more independent Tier A sources, this drug in the cohort, the nutrient directly measured, consistent direction, clinically meaningful magnitude, a named mechanism, no substantial contradicting Tier A evidence. Red

Limits on what this shows

  • Key negative/null findings: By week 26-52, group-mean calcium sits centrally within the normal range rather than persistently elevated, and the label states elevated values in trials were generally managed by dose or supplement adjustment, arguing against an unmanageable or progressive process at recommended dosing and titration.
  • At-risk subgroups: Patients starting therapy or having a recent dose increase (hypercalcemia risk); patients who abruptly stop the drug, miss doses for 3 or more days, or use two injections to reach their dose (hypocalcemia and dose-variability risk, per label warning); patients on digoxin, for whom transient hypercalcemia can potentiate digitalis toxicity.
  • Counter-evidence on record: The 2-year, drug-specific renal-function follow-up publication (Journal of Clinical Endocrinology & Metabolism, reported via PMC13525197) could not be opened during this review (PMC returned a reCAPTCHA bot-verification challenge on every attempt); it is listed in Sources but not used as supporting evidence here beyond its title and the 1-year data (Rejnmark et al) that could be opened.

Regulatory status

Labeling requires serum calcium monitoring 7-10 days after the first dose and after any dose change, then at least every 4-6 weeks at maintenance; warns explicitly of both serious hypercalcemia (highest risk when starting or increasing dose) and serious hypocalcemia (highest risk with abrupt discontinuation or a missed dose of 3 or more days, but possible at any time even on a stable dose).

Population evidence

DailyMed label and the phase 3 PaTHway trial (Khan et al, JBMR 2023; Clarke et al, JCEM 2025), n=82 (61 palopegteriparatide, 21 placebo). Hypercalcemia: 54.1% (33/61) of treated subjects had albumin-corrected calcium above 10.6 mg/dL at some point versus 9.5% (2/21) on placebo; 13.1% (8/61) exceeded 12 mg/dL versus 0% on placebo; symptomatic hypercalcemia occurred in 8% of treated subjects, all within the first 3 months; one subject who self-administered a roughly 3-fold overdose for 7+ days reached a serum calcium of 16.1 mg/dL and required hospitalization. By week 26 and 52, mean albumin-adjusted calcium in the full treated cohort had settled to 8.9 mg/dL (within the 8.3-10.6 mg/dL normal range), and 86% maintained normocalcemia at week 52.

Mechanism

Named, and the drug's intended mechanism rather than an incidental effect: PTH1-receptor activation mobilizes bone calcium, increases renal tubular calcium reabsorption, and (via stimulated calcitriol synthesis) increases intestinal calcium absorption. Because the patient's own parathyroid gland cannot buffer or shut this off, dosing precision substitutes for the physiologic feedback loop a person with an intact parathyroid gland would have.

Counter-evidence held on record

This entry must never be presented as a simple "excess" or "deficiency" finding in isolation: it is a bidirectional, dosing-sensitive risk unique to a replacement therapy in a patient with no functioning parathyroid reserve. It should never prompt a reader to independently increase or decrease dietary calcium, and any question about a specific calcium reading belongs with the prescriber, since both directions here carry documented serious-adverse-event risk.

Phosphate, corrected toward mid-normal from a high-normal baseline, no hypophosphatemia reported

Orange — Moderate

See study details

Palopegteriparatide lowers serum phosphate from a baseline that runs at the high end of normal (consistent with untreated hypoparathyroidism's characteristic hyperphosphatemia) toward mid-normal, a real, drug-specific, and clinically intended correction rather than a depletion effect.

Full detail and limits

What the grade means here: At least one Tier A source with this drug in the cohort showing a real but bounded deficit: an exposure window, a subgroup, low frequency, or a functional rather than circulating deficit. Orange

Limits on what this shows

  • Key negative/null findings: No hypophosphatemia was reported as an adverse event in either the 26-week or 52-week PaTHway publications reviewed; the endpoint value (3.7-3.8 mg/dL) sits centrally within, not below, the normal range.
  • At-risk subgroups: Not separately quantified for phosphate specifically; by mechanism, a patient who is over-dosed or who has unusually high phosphaturic sensitivity would be the plausible, though unquantified, group for a low-phosphate excursion.
  • Counter-evidence on record: None found contradicting the direction or the absence of clinical hypophosphatemia; the 2-year follow-up publication that might extend this window could not be opened (see Calcium entry).

Regulatory status

Described directly in the label's pharmacodynamics section alongside calcium; no phosphate-specific monitoring requirement beyond the routine calcium/phosphate panel already required for the drug.

Population evidence

PaTHway phase 3 trial, drug in cohort. 26-week results (Khan et al, JBMR 2023): mean serum phosphate 4.2 (SD 0.6) mg/dL at baseline falling to 3.8 (SD 0.6) mg/dL at week 26 on palopegteriparatide, versus 3.9 to 3.9 mg/dL on placebo (essentially unchanged). 52-week results (Clarke et al, JCEM 2025): mean serum phosphate 3.7 (SD 0.7) mg/dL, within the normal reference range. Calcium-phosphate product fell from 37.1 to 33.9 mg²/dL² on drug versus 33.7 to 31.7 on placebo, both remaining below the 55 mg²/dL² safety threshold cited in that publication.

Mechanism

Named: PTH1-receptor activation in the renal proximal tubule reduces sodium-phosphate cotransporter activity, producing phosphaturia; in hypoparathyroidism this reverses the disease's own characteristic renal phosphate retention (hyperphosphatemia), so the direction here is corrective, not an adverse drug effect layered onto a normal system.

Counter-evidence held on record

Do not present this as a phosphate-deficiency risk requiring supplementation; it is the drug correcting the hyperphosphatemia typical of untreated hypoparathyroidism, and phosphate is already part of the routine monitoring built into standard care for this drug.

Vitamin D axis, active calcitriol restored endogenously, exogenous active vitamin D discontinued in nearly all patients

Orange — Moderate

See study details

Palopegteriparatide stimulates the patient's own conversion of storage vitamin D into active calcitriol strongly enough that 95-100% of trial participants discontinued exogenous active vitamin D by week 52 while maintaining a normal active-hormone level, a real, drug-specific, and restorative axis shift.

Full detail and limits

What the grade means here: At least one Tier A source with this drug in the cohort showing a real but bounded deficit: an exposure window, a subgroup, low frequency, or a functional rather than circulating deficit. Orange

Limits on what this shows

  • Key negative/null findings: The active hormone level is preserved and normal even as exogenous supplementation is withdrawn entirely, which is itself evidence against a net vitamin D deficit; this is reported as an axis restoration, not a depletion, consistent with hard rule 3's requirement that a functional/companion marker be checked before treating a falling storage-form number as meaningful on its own.
  • At-risk subgroups: Not separately quantified; patients whose baseline storage 25-hydroxyvitamin D is already low before starting therapy are the plausible, though untested, group where the modest further decline could matter.
  • Counter-evidence on record: No unsupplemented or vitamin-D-naive palopegteriparatide cohort was found; all reviewed trial participants had established conventional (calcium/vitamin D) therapy at baseline, limiting generalization to a treatment-naive population.

Regulatory status

Described in the label's pharmacodynamics section; the label notes active-vitamin-D requirements are typically reduced or discontinued during dose titration, and the primary efficacy endpoint in the pivotal trial explicitly required independence from active vitamin D.

Population evidence

PaTHway trial, drug in cohort. Baseline mean active vitamin D use was 0.75 mcg/day (calcitriol, n=70) or 2.3 mcg/day (alfacalcidol, n=12) before starting palopegteriparatide. At week 26 (Khan et al, JBMR 2023), mean 25-hydroxyvitamin D fell from 43.2 (SD 11.9) to 36.4 (SD 12.0) ng/mL on drug (placebo essentially unchanged, 41.1 to 42.2), while mean active 1,25-dihydroxyvitamin D was preserved (38.5 to 39.6 pg/mL). At week 52 (Clarke et al, JCEM 2025), with 100% of the 78 evaluable participants off active vitamin D entirely, mean active 1,25-dihydroxyvitamin D was 41.5 (SD 16.2) pg/mL and 25-hydroxyvitamin D was 39.0 (SD 13.6) ng/mL, both within normal ranges.

Mechanism

Named: PTH1-receptor activation stimulates renal 1-alpha-hydroxylase, accelerating conversion of storage 25-hydroxyvitamin D into active 1,25-dihydroxyvitamin D; the modest storage-form decline is the expected, mechanistic counterpart of that accelerated conversion, occurring alongside discontinuation of exogenous active vitamin D rather than reduced dietary intake.

Counter-evidence held on record

Do not present this as evidence that palopegteriparatide depletes vitamin D; the active hormone is preserved while exogenous active vitamin D is withdrawn under prescriber supervision. This should surface only as a reason dose titration of vitamin D and calcium is managed by a prescriber, never as a prompt to add vitamin D on a reader's own initiative.

Magnesium, a class-level theoretical concern directly tested and not replicated in this drug's own trial data

Yellow — Low

See study details

A mechanism for renal magnesium loss exists via the same PTH1-receptor tubular pathway that moves calcium and phosphate, and this project's teriparatide dossier documents a real, substantial magnesium-wasting signal for that class relative, but palopegteriparatide's own pivotal-trial data show stable magnesium through 52 weeks.

Full detail and limits

What the grade means here: Mechanistic plausibility only (Tier B), or class extrapolation (Tier C) with no drug-specific human status data; also used for context flags and interactions running the other direction. Yellow

Limits on what this shows

  • Key negative/null findings: This is itself the primary finding to report here: a direct, drug-specific, tier A measurement across 52 weeks in the same trial that also generated the Calcium and Phosphate entries shows no meaningful magnesium decline, despite a plausible shared mechanism and a real signal in a related molecule.
  • At-risk subgroups: Not established for palopegteriparatide; older age and lower baseline magnesium were risk factors in the teriparatide cohort, and would be the plausible group to watch if a palopegteriparatide-specific signal emerges with longer follow-up or a larger population than the 61-82 patients studied so far.
  • Counter-evidence on record: The reassuring finding is the counter-evidence itself; it should be weighed against the trial's modest size (61 treated subjects) and duration relative to the teriparatide cohort, so it does not fully exclude a smaller or later-onset effect.

Regulatory status

Not addressed as a warning in labeling; pre-randomization eligibility for the pivotal trial required serum magnesium ≥1.3 mg/dL and below the upper limit of normal, so the trial population started within normal range.

Population evidence

PaTHway trial, drug in cohort. Mean magnesium 2.1 (SD 0.2) mg/dL at baseline and 2.2 (SD 0.1) mg/dL at week 26 on palopegteriparatide (placebo 2.0 to 2.0 mg/dL), and 2.1 (SD 0.2) mg/dL at week 52 (Khan et al 2023; Clarke et al 2025). No hypomagnesemia was reported as an adverse event in either publication. By contrast, this project's teriparatide dossier reports a single-center retrospective cohort (Begin et al, JBMR 2018, n=53) finding hypomagnesemia in 35.9% of teriparatide-treated patients with a statistically significant decline at every timepoint (p<0.0001), graded orange there; that finding is class-level (tier C) context for palopegteriparatide, not itself palopegteriparatide evidence, since the two drugs were not studied in the same cohort.

Mechanism

Present in principle: PTH1-receptor activation affects distal tubular magnesium handling, the same class of mechanism (renal tubular handling, mechanism class C) implicated in the Calcium and Phosphate entries above and in teriparatide's own magnesium finding.

Counter-evidence held on record

Do not present this as evidence that palopegteriparatide depletes magnesium; the drug's own data show no decline. It is reported here specifically so a reader does not assume, from teriparatide's known magnesium effect, that the same risk automatically applies to a different molecule with different dosing kinetics. Periodic magnesium monitoring alongside routine calcium/phosphate labs remains reasonable rather than supplementation.

The five body-system areas

Each finding is counted once, in a single area. Where a study is mentioned in a second area it is context only.

Mitochondrial Burden

Each finding below is counted once, in this area only.

Mitochondrial burden, a PTH-excess cell-culture mechanism, not this drug's therapeutic replacement context

Yellow — Low

See study details

An in vitro study links PTH receptor signaling to mitochondrial calcium overload and reactive oxygen species generation, but the model is pathologic PTH excess in endothelial cells studied for cardiovascular disease, not PTH(1-34) replacement dosing in hypoparathyroidism, and no palopegteriparatide-specific data exist.

Full detail, limits and 1 references

What the grade means here: Mechanistic plausibility only (Tier B), or class extrapolation (Tier C) with no drug-specific human status data; also used for context flags and interactions running the other direction. Yellow

Limits on what this shows

  • Key negative/null findings: No human or in vivo data, and no data using PTH(1-34) or any TransCon PTH construct specifically, were found; the entry's central limitation is that it models excess PTH exposure, the opposite clinical intent from a replacement therapy titrated toward normocalcemia.
  • At-risk subgroups: Not established for this drug; by extension of the mechanism, the periods of transient supraphysiologic exposure documented in the Calcium entry (early treatment, dose increases, the reported overdose case) would be the plausible, though untested, window where this mechanism could theoretically be most relevant.
  • Counter-evidence on record: None found specifically contradicting the cell-culture mechanism; the counter-evidence is one of relevance and context, not of direction, since no study has tested whether it manifests at this drug's therapeutic exposure.

Regulatory status

Not addressed in labeling.

Population evidence

Gambardella et al, Oxidative Medicine and Cellular Longevity, 2018. In vitro study, bovine aortic endothelial cells, PTH 0.1 nM, studied in the context of PTH-associated cardiovascular risk (not a hypoparathyroidism or PTH-replacement model). Total ROS increased 1.35-fold at 1 hour (p<0.01); mitochondrial ROS increased 0.348-fold at 1 hour (p<0.05); the mitochondrial calcium uniporter inhibitor Ru360 reduced mitochondrial ROS production (p<0.0001), and the mitochondria-targeted antioxidant MitoTEMPO reduced downstream endothelial dysfunction, both supporting a mitochondrial-calcium-dependent mechanism.

Mechanism

Named: PTH receptor activation triggers cytosolic calcium mobilization; the mitochondrial calcium uniporter imports this calcium into mitochondria, producing calcium overload that stimulates electron-transport-chain leakage and ROS generation. This is a receptor-activation mechanism shared in principle with any PTH1R agonist, including palopegteriparatide, but the study models supraphysiologic/pathologic PTH exposure relevant to elevated endogenous PTH states, not the corrective, replacement-level dosing this drug is titrated to achieve.

Counter-evidence held on record

Do not present this as evidence that palopegteriparatide causes mitochondrial harm at therapeutic dosing; it is a cell-culture mechanism from PTH-excess cardiovascular research, not a finding in treated hypoparathyroidism patients, and must never be used to suggest mitochondrial-support supplementation. Shares its underlying source with the Oxidative stress entry below; see Overlap map.

Oxidative Stress

Each finding below is counted once, in this area only.

Oxidative stress, genuinely conflicting directions depending on PTH exposure pattern

Yellow — Low

See study details

One PTH-excess cell-culture study points toward mitochondrial ROS generation, while two independent teriparatide animal studies point toward reduced oxidative stress markers; no palopegteriparatide-specific data exist, and this entry reports the tension rather than resolving it in either direction.

Full detail and limits

What the grade means here: Mechanistic plausibility only (Tier B), or class extrapolation (Tier C) with no drug-specific human status data; also used for context flags and interactions running the other direction. Yellow

Limits on what this shows

  • Key negative/null findings: No human oxidative-stress-marker data exist for palopegteriparatide, teriparatide, or endogenous PTH replacement in hypoparathyroidism specifically; a separate, tangential surgical cohort study (Kaçmaz et al, Endocrine, 2015, thyroidectomy versus thyroparathyroidectomy patients) found elevated malondialdehyde and nitric oxide with reduced catalase in both surgical groups versus controls, but did not find a difference attributable to parathyroid status specifically, and thyroid hormone level (FT4) predicted the oxidative marker instead, arguing against attributing this surgical-cohort signal to hypoparathyroidism or its treatment.
  • At-risk subgroups: Not established for this drug.
  • Counter-evidence on record: The two directions are, in effect, counter-evidence to each other; both are reported rather than one being selected, per the requirement to record findings that weaken as well as strengthen a claim.

Regulatory status

Not addressed in labeling.

Population evidence

Harmful-direction: Gambardella et al 2018 (see Mitochondrial burden entry), PTH-excess endothelial cell model, ROS increased. Protective-direction: two teriparatide (PTH 1-34) animal/cell studies, tier C class extrapolation for palopegteriparatide. Xiong et al, Frontiers in Pharmacology, 2025: 138 male Sprague-Dawley rats, spinal cord injury model, teriparatide 20 mcg/kg/day subcutaneously for 14 days. Malondialdehyde fell (day 14: 0.42 ± 0.03 vs saline 1.22 ± 0.13, p<0.001); glutathione peroxidase rose (0.5 ± 0.03 vs 0.16 ± 0.03, p<0.001); Nrf2 rose (2.87 ± 0.13 vs 0.82 ± 0.06, p<0.001) with elevated downstream HO-1 (251.42 ± 2.72 vs 51.77 ± 1.05, p<0.001) and SOD2 (179.66 ± 10.67 vs 10.16 ± 1.15, p<0.001). A second teriparatide study (MLO-Y4 osteocytes and a dexamethasone-induced osteoporosis rat model, cited in this project's teriparatide dossier) similarly found reduced reactive oxygen species and partially restored SOD2/catalase expression with teriparatide co-treatment.

Mechanism

Both directions have named mechanisms that are not mutually exclusive: PTH-excess/supraphysiologic exposure driving mitochondrial-calcium-dependent ROS generation (Gambardella), versus PTH(1-34) at therapeutic, intermittent dosing activating the Nrf2/HO-1 antioxidant-response pathway (Xiong). The unresolved question for palopegteriparatide specifically is which pattern its near-continuous, replacement-level exposure more closely resembles, which no source reviewed addresses directly.

Counter-evidence held on record

Do not present this as either a clear harm or a clear benefit; the literature genuinely conflicts depending on whether PTH exposure is excess/pathologic or therapeutic/replacement, and no data exist for this drug or this disease state directly. Never use this entry to recommend antioxidant supplementation. Shares its harmful-direction source with the Mitochondrial burden entry above; see Overlap map.

Copper and Iron Balance

Copper and iron are assessed separately. Nothing here is counted twice.

Copper

Not graded — disclosed evidence gap

See study details

No tier B or C evidence, and no circulating consumer claim, connecting palopegteriparatide, teriparatide, or PTH replacement generally to copper status was found.

Full detail and limits

What the grade means here: Nothing has been measured here, so this finding cannot be graded. That does not establish either safety or harm, and it is not the same as a White result. Ungraded

Limits on what this shows

  • Why no grade: The dual condition for ungraded is met. Channels tried: (1) DailyMed label, no copper content anywhere in the prescribing information; (2) Crossref API query for palopegteriparatide plus copper, returned only generic regulatory/reimbursement/case-report entries about palopegteriparatide with no copper content; (3) PubMed search-listing pages for "hypoparathyroidism AND copper" across the full first page of results, which returned only case reports of Wilson's disease (copper-overload disease) causing hypoparathyroidism as a downstream complication of copper deposition damaging the parathyroid glands themselves, the reverse causal direction from what this dossier grades (copper affecting the parathyroid, not PTH or its replacement affecting copper), and were explicitly not used to support a grade here; (4) drugs.com's palopegteriparatide interaction checker (131 listed drug interactions), no supplement, vitamin, or mineral entries at all. No mechanism from the pharmacokinetic prescreen supports a plausible pathway either: this is a subcutaneously injected peptide prodrug with no gastrointestinal absorption step to chelate or compete at, no CYP450 involvement, and no described copper-cofactor dependency in its clearance pathway. Access note: a further, more targeted attempt to open a 1976 case-series abstract on copper and zinc metabolism in primary hyperparathyroidism (a different clinical entity, excess endogenous PTH from a tumor, not PTH replacement) was blocked by a repeated 429 rate-limit response from PubMed; the Europe PMC REST API and the Semantic Scholar API also returned repeated 429 responses across separate attempts during this review, and this session's WebSearch allowance was exhausted before every possible phrasing could be tried through that channel. These are disclosed as tooling limitations, not treated as further confirming the gap.

Iron

Not graded — disclosed evidence gap

See study details

No tier B or C evidence, and no circulating consumer claim, connecting palopegteriparatide, teriparatide, or PTH replacement generally to iron status (ferritin, transferrin saturation, serum iron, hepcidin) was found; the adjacent teriparatide hematopoietic stem cell data (see Oxygen delivery/utilization) do not measure iron status and were deliberately not used to support a grade here.

Full detail and limits

What the grade means here: Nothing has been measured here, so this finding cannot be graded. That does not establish either safety or harm, and it is not the same as a White result. Ungraded

Limits on what this shows

  • Why no grade: The dual condition for ungraded is met. Channels tried: (1) DailyMed label, no iron content anywhere in the prescribing information; (2) Crossref API query for palopegteriparatide plus iron, returned only generic palopegteriparatide entries (drug monographs, case reports, reimbursement reviews) with no iron content; (3) PubMed search-listing pages for "hypoparathyroidism AND iron status" across the full first page of results, which returned only beta-thalassemia (iron-overload disease) literature describing hypoparathyroidism as one of several downstream endocrine complications of chronic iron overload and chelation therapy, again the reverse causal direction from what this dossier grades, and were explicitly not used to support a grade here; (4) drugs.com's interaction checker, no supplement, vitamin, or mineral entries. The hematopoietic stem cell mobilization finding under Oxygen delivery/utilization concerns marrow progenitor activity in a different molecule (teriparatide), not ferritin, transferrin saturation, or another direct iron-status marker; using it here would double count one signal as two findings, so it was intentionally excluded. Access note: as with Copper, the Europe PMC REST API and Semantic Scholar API returned repeated 429 rate-limit responses across separate attempts, and this session's WebSearch allowance was exhausted before every possible phrasing could be run through that channel; this is a disclosed tooling limitation, not a confirmed absence beyond what the channels actually used could show.

Gut Microbiome Risk

Each finding below is counted once, in this area only.

Gut microbiome risk, opposite mouse-model mechanisms for continuous versus intermittent PTH exposure, with reassuring clinical bone data

Yellow — Low

See study details

A mechanistic review distinguishes a gut-microbiota-dependent bone-loss pathway triggered by continuous PTH exposure in mouse infusion models from a protective, SCFA-mediated pathway triggered by intermittent PTH exposure, a distinction directly relevant to palopegteriparatide's sustained-release design, though this drug's own skeletal-dynamics data show normalization rather than loss.

Full detail and limits

What the grade means here: Mechanistic plausibility only (Tier B), or class extrapolation (Tier C) with no drug-specific human status data; also used for context flags and interactions running the other direction. Yellow

Limits on what this shows

  • Key negative/null findings: Important counter-evidence specific to this drug: the phase 2 PaTH Forward trial's 214-week skeletal-dynamics data (Turner et al, SfE BES 2026 abstract) report that elevated baseline bone mineral density Z-scores (a known feature of untreated hypoparathyroidism's abnormally low bone turnover) trended toward age- and sex-matched normal values and stabilized after 26 weeks, while bone turnover markers (CTx, P1NP) rose from low-normal at baseline to normal and remained stable through 214 weeks, without a described progression to bone loss. This argues against the mouse cPTH bone-loss mechanism manifesting clinically at this drug's dosing over more than 4 years of follow-up, though no study reviewed measured gut microbiome composition in palopegteriparatide-treated patients directly.
  • At-risk subgroups: Not established; no palopegteriparatide-specific microbiome or gastrointestinal-risk subgroup data exist.
  • Counter-evidence on record: The 214-week skeletal-dynamics normalization data (above) and the teriparatide-specific protective microbiome finding both run counter to the theoretical cPTH-bone-loss concern; no study was found showing an adverse microbiome or bone outcome specifically attributable to palopegteriparatide's continuous-exposure design.

Regulatory status

Not addressed in labeling.

Population evidence

Pacifici, Journal of Clinical Endocrinology & Metabolism, 2021 (narrative review, mouse and human literature synthesis, not itself a primary palopegteriparatide or teriparatide study). Describes continuous PTH (cPTH, delivered by infusion pump in mouse models) as requiring bacterial lipopolysaccharide and flagellin to stimulate TNF-positive T cells and Th17 cells that migrate to bone marrow and drive RANKL-mediated bone loss, versus intermittent PTH (iPTH, daily-bolus dosing as with teriparatide) requiring microbiota-derived butyrate to promote regulatory T cell differentiation and Wnt10b-mediated bone formation. Separately, a real human, drug-specific study for the class relative (Deng, Su, Tian, Archives of Osteoporosis, 2026; non-randomized, open-label, 108 patients, 68 on teriparatide 20 mcg/day, 40 on denosumab, 6 months, fecal 16S rDNA sequencing) found teriparatide significantly enriched two short-chain-fatty-acid-producing genera, Dubosiella (correlated with L4 bone mineral density) and Butyrivibrio (correlated with L2 and hip bone mineral density), a protective compositional shift, not disruption.

Mechanism

Named and directly relevant to this drug's design: palopegteriparatide is specifically engineered (TransCon sustained-release linker, approximately 60-hour apparent half-life of released PTH versus teriparatide's approximately 1 hour) to maintain more continuous PTH1R occupancy than teriparatide's daily bolus-and-clearance pattern, which is mechanistically closer to the cPTH category in the Pacifici review than to the iPTH/teriparatide category, though it is not identical to the pump-infusion supraphysiologic exposure used in the mouse cPTH experiments the review describes.

Counter-evidence held on record

Do not present this as an established microbiome-disruption risk; it is a theoretical mechanism from mouse infusion studies that this drug's own multi-year human bone data do not appear to bear out, reported here to satisfy the required category and to flag a genuine, drug-specific mechanistic nuance (continuous versus intermittent PTH exposure) rather than because harm has been observed. Never use this to suggest probiotic supplementation.

Oxygen and ATP Output

Oxygen delivery and ATP production are assessed separately. Nothing here is counted twice.

Oxygen delivery/utilization, carried forward only via teriparatide extrapolation, no palopegteriparatide or hypoparathyroidism-specific data

Yellow — Low

See study details

The only PTH(1-34)-linked human hematologic signal found is a teriparatide cohort showing transient hematopoietic stem cell mobilization without a red blood cell change; no palopegteriparatide-specific data exist, and the DailyMed label reports no hematologic abnormalities in the pivotal trial.

Full detail, limits and 1 references

What the grade means here: Mechanistic plausibility only (Tier B), or class extrapolation (Tier C) with no drug-specific human status data; also used for context flags and interactions running the other direction. Yellow

Limits on what this shows

  • Key negative/null findings: The teriparatide cohort's explicit finding of no red blood cell change is the most informative result available and is reported here as the operative null for the oxygen-delivery question; the DailyMed label's own adverse-reaction and laboratory-findings tables for palopegteriparatide list no hematologic category at all, a further (label-level) null specific to this drug.
  • At-risk subgroups: Not established for palopegteriparatide.
  • Counter-evidence on record: No source found contradicting the direction; the main limitation is that the supporting evidence is entirely about a different molecule with different exposure kinetics, and this entry is graded and framed accordingly rather than treated as if it were drug-specific.

Regulatory status

Not addressed in labeling; no anemia, hemoglobin, or hematocrit signal appears among the adverse reactions or laboratory findings sections reviewed for this drug.

Population evidence

Yu et al, Journal of Bone and Mineral Research, 2014, tier C class extrapolation (teriparatide, not palopegteriparatide, in the cohort). Prospective longitudinal trial, 23 postmenopausal women (18 with full longitudinal data), teriparatide 20 mcg subcutaneously daily for 24 months. Hematopoietic stem cells (CD34+/CD45-moderate) increased 40% ± 14% by month 3 (p=0.004), remained elevated at 6 months (p=0.013) and 18 months (p=0.044), returned to baseline by 24 months; red blood cell counts showed no significant change throughout.

Mechanism

Proposed, not established: PTH signaling is known to act on bone-marrow osteoblastic niche cells that regulate hematopoietic stem cell quiescence and mobilization, plausibly extending to any PTH1R agonist including palopegteriparatide, but this has not been tested for this drug, and the fundamentally different exposure pattern (near-continuous versus teriparatide's daily bolus) means the same marrow-niche signaling dynamics cannot be assumed to transfer unchanged.

Counter-evidence held on record

Do not present this as an established anemia or oxygen-delivery risk for palopegteriparatide; the only supporting human data are from a different PTH(1-34) drug with different dosing kinetics, and this drug's own label reports no hematologic signal at all. Never attribute a hemoglobin change in a hypoparathyroidism patient to this drug without excluding other causes.

ATP production, carried forward only via teriparatide's osteoblast-specific glycolysis finding, not a systemic claim

Yellow — Low

See study details

A narrative review characterizes a mouse osteoblast study in which teriparatide favors glycolytic over mitochondrial ATP generation as part of its own bone-anabolic mechanism; this is tissue-specific cell biology in a different molecule, not a systemic energy claim, and no palopegteriparatide data exist.

Full detail, limits and 1 references

What the grade means here: Mechanistic plausibility only (Tier B), or class extrapolation (Tier C) with no drug-specific human status data; also used for context flags and interactions running the other direction. Yellow

Limits on what this shows

  • Key negative/null findings: No direct ATP-output or whole-body energy-expenditure measurement in palopegteriparatide- or teriparatide-treated humans was found; per the tightened evidentiary standard for functional claims, a pathway-level substrate shift in one cell type in a different molecule is not the same as a systemic ATP-production claim for this drug, and this entry is written and framed accordingly.
  • At-risk subgroups: Not applicable; cell-type-specific finding in a different molecule, not a patient subgroup risk.
  • Counter-evidence on record: None found directly; the gap is the absence of any systemic energetic measurement for either molecule, not a contradicting result.

Regulatory status

Not addressed in labeling. Patient-reported outcome data (Rubin et al, JCEM 2026, PaTH Forward trial extension, this drug specifically) show large, sustained improvements in SF-36v2 Physical and Mental Component Summary scores and hypoparathyroidism-specific symptom scores through 110 weeks, but these are clinical, whole-person functioning and symptom measures, not a measurement of cellular ATP output, and are not used here to support this entry per hard rule 2 (a clinical outcome is not a nutrient/energy-metabolism finding).

Population evidence

Journal of Bone and Mineral Research review, 2024 (DOI 10.1093/jbmr/zjae088), tier C class extrapolation. States that teriparatide "was shown to enhance bone formation by activating aerobic glycolysis and preventing glucose entry into the TCA cycle via IGF signaling in mouse osteoblasts," and that pharmacologically forcing glucose back into the TCA cycle (dichloroacetate) abolished the PTH-induced bone-mass increase. The primary mouse study behind this claim (the review's reference 44) was not independently opened during this review; this entry rests on the review's own characterization, disclosed here rather than presented as if the primary paper were read directly.

Mechanism

Named: aerobic glycolysis substitutes for mitochondrial oxidative phosphorylation as the dominant ATP source in differentiating osteoblasts under PTH(1-34) receptor signaling; this is upstream, tissue-specific cell biology in bone-forming cells, not a whole-body ATP or energy-expenditure measurement, and has not been tested for palopegteriparatide or in a hypoparathyroidism disease context.

Counter-evidence held on record

Do not present this as evidence that palopegteriparatide increases or decreases whole-body energy or causes fatigue; the source describes bone-cell substrate preference in a different PTH(1-34) molecule, not a systemic ATP deficit, and the patient-reported energy/functioning improvements seen with palopegteriparatide itself are a clinical outcome, not an ATP measurement, and are not used to inflate this entry. Shares its underlying review source with the Mitochondrial burden entry's cross-drug context; see Overlap map.

All references used above
  1. YORVIPATH (palopegteriparatide) injection, for subcutaneous use, prescribing information. — DailyMed, U.S. National Library of Medicine. Regulatory label, setid a1fa23fd-c434-443e-9a17-5750578c8602. Initial U.S. approval 2024.
  2. Khan AA, Rejnmark L, Rubin M, et al. Efficacy and Safety of Parathyroid Hormone Replacement With TransCon PTH in Hypoparathyroidism: 26-Week Results From the Phase 3 PaTHway Trial. — Journal of Bone and Mineral Research. 2023;38(1):14-25. Phase 3 RCT, n=82 (61 drug, 21 placebo). DOI: 10.1002/jbmr.4726.
  3. Clarke BL, Khan AA, Rubin MR, et al. Efficacy and Safety of TransCon PTH in Adults With Hypoparathyroidism: 52-Week Results From the Phase 3 PaTHway Trial. — Journal of Clinical Endocrinology & Metabolism. 2025;110(4):951-960. Same phase 3 trial, open-label extension. DOI: 10.1210/clinem/dgae693.
  4. Rejnmark L, Gosmanova EO, Khan AA, et al. Palopegteriparatide Treatment Improves Renal Function in Adults with Chronic Hypoparathyroidism: 1-Year Results from the Phase 3 PaTHway Trial. — Advances in Therapy. 2024;41(6):2500-2518. Post hoc analysis of the same phase 3 trial, n=82. DOI: 10.1007/s12325-024-02843-8.
  5. Sustained improvement in renal function with palopegteriparatide in adults with chronic hypoparathyroidism: 2-year results from the phase 3 PaTHway trial. — Journal of Clinical Endocrinology & Metabolism (per PubMed indexing). Extension of the renal-function analysis above to 2 years.Could not be opened: PMC returned a reCAPTCHA bot-verification challenge page on every fetch attempt during this review. Listed only, not used as supporting evidence beyond its title; the 1-year data from the same research program (source 4 above) was opened and is used instead.
  6. Rubin M, Palermo A, Vokes T, et al. Patient-reported outcomes in palopegteriparatide-treated adults with hypoparathyroidism: PaTH Forward trial extension. — Journal of Clinical Endocrinology & Metabolism. 2026;111(4):945-952. Phase 2 trial extension, n=59 (57 through week 110). DOI: 10.1210/clinem/dgaf653.
  7. Turner J, et al. Improved Skeletal Dynamics in Adults Treated with Palopegteriparatide for Chronic Hypoparathyroidism: 214-Week Results from the Phase 2 PaTH Forward Trial. — Society for Endocrinology BES 2026 conference abstract, Harrogate, UK. Phase 2 trial extension, n=56 (95% continuation through week 214).
  8. Gambardella J, Fiordelisi A, Spigno L, et al. Parathyroid Hormone Causes Endothelial Dysfunction by Inducing Mitochondrial ROS and Specific Oxidative Signal Transduction Modifications. — Oxidative Medicine and Cellular Longevity. 2018:9582319. In vitro study, bovine aortic endothelial cells, PTH-excess/cardiovascular-risk context. PMID: 30662585. DOI: 10.1155/2018/9582319.
  9. Pacifici R. Role of Gut Microbiota in the Skeletal Response to PTH. — Journal of Clinical Endocrinology & Metabolism. 2021. Narrative review distinguishing continuous versus intermittent PTH exposure mechanisms in mouse models. DOI: 10.1210/clinem/dgaa895.
  10. Deng J, Su S, Tian L. A clinical study on the effects of teriparatide and denosumab on bone metabolism and gut microbiota in osteoporotic fracture patients. — Archives of Osteoporosis. 2026. Non-randomized, open-label, n=108 (68 teriparatide, 40 denosumab), 6 months, 16S rDNA fecal sequencing. DOI: 10.1007/s11657-026-01697-7.
  11. Multifaceted roles of mitochondria in osteoblasts: from energy production to mitochondrial-derived vesicle secretion. — Journal of Bone and Mineral Research. 2024;39(9):1205. Narrative review; characterizes a mouse osteoblast teriparatide aerobic-glycolysis study (its own reference 44, not independently opened during this review). DOI: 10.1093/jbmr/zjae088.
  12. Yu EW, Kumbhani R, Siwila-Sackman E, DeLelys M, Preffer FI, Leder BZ, Wu JY. Teriparatide (PTH 1-34) Treatment Increases Peripheral Hematopoietic Stem Cells in Postmenopausal Women. — Journal of Bone and Mineral Research. 2014;29(6):1380. Prospective longitudinal trial, n=23 (18 with longitudinal data), teriparatide 20 mcg/day SC, 24 months.
  13. Xiong M, et al. Teriparatide mitigates oxidative stress following spinal cord injury and enhances neurological recovery via the Nrf2/HO-1 signaling pathway. — Frontiers in Pharmacology. 2025;16:1538857. In vivo rat study, n=138, teriparatide 20 mcg/kg/day SC, 14 days. DOI: 10.3389/fphar.2025.1538857.
  14. Kaçmaz M, Atmaca M, Arslan A, Demir H, Ozbay MF. Oxidative stress in patients with thyroidectomy and thyroparathyroidectomy under replacement therapy. — Endocrine. 2015;48(3):908-915 (published online 2014). Cross-sectional, n=39 surgical patients (19 thyroidectomy, 20 thyroparathyroidectomy) plus 20 controls. Did not isolate a hypoparathyroidism-specific effect; thyroid hormone (FT4) predicted the oxidative marker instead. DOI: 10.1007/s12020-014-0270-6.
  15. PubMed search listing: "hypoparathyroidism AND copper". — Search-listing page review (not a single citable study); returned Wilson's disease case reports/reviews describing hypoparathyroidism as a complication of copper-overload disease, the reverse causal direction from this dossier's Copper entry. Used only to document the absence of usable evidence.
  16. PubMed search listing: "hypoparathyroidism AND iron status". — Search-listing page review (not a single citable study); returned beta-thalassemia (iron-overload) literature describing hypoparathyroidism as a downstream endocrine complication, the reverse causal direction from this dossier's Iron entry. Used only to document the absence of usable evidence.
  17. Crossref API queries for palopegteriparatide + copper, palopegteriparatide + iron, and palopegteriparatide + microbiome. — Bibliographic search only (api.crossref.org), used to confirm the absence of drug-specific literature for the Copper, Iron, and (in part) Gut microbiome risk entries. Not a citable study; recorded here for audit transparency.
  18. Palopegteriparatide interactions checker. — Drugs.com. Consumer drug-interaction listing (131 drug-drug interactions, zero supplement/vitamin/mineral entries); used to support the empty Fails verification section and the Copper/Iron ungraded disclosures.
  19. WHO Collaborating Centre for Drug Statistics Methodology, ATC/DDD Index, code H05AA05. — Used to confirm the ATC classification for palopegteriparatide ("Parathyroid hormones and analogues").
  20. Palopegteriparatide. — Wikipedia. Used only to cross-check EU (November 2023) and US (August 2024) approval dates against the DailyMed label; not used as a clinical-evidence source for any graded entry.