Desoxycorticosterone Pivalate Duration of Action and Individualized Dosing Intervals in Dogs with Primary Hypoadrenocorticism

Clinical characteristics, treatment, and outcomes of hypoadrenocorticism in dogs

OBJECTIVES

To determine the long-term survival of dogs with hypoadrenocorticism during the period that desoxycorticosterone pivalate has become widely used. Secondary goals were to compare age at diagnosis, median survival times, and age at death for dogs with hyponatraemic and/or hyperkalaemic hypoadrenocorticism and eunatraemic eukalaemic hypoadrenocorticism, and to determine the frequency of glucocorticoid-related side effects in these dogs.

MATERIALS AND METHODS

Retrospective cohort study with data collected from medical records and from a questionnaire sent to owners of affected dogs.

RESULTS

141 cases were identified; 125 had spontaneous hypoadrenocorticism and 16 had iatrogenic hypoadrenocorticism secondary to treatment of hyperadrenocorticism. Dogs with spontaneous hyponatraemic and/or hyperkalaemic hypoadrenocorticism were significantly younger at the time of diagnosis (median age: 5.1, range: 0.8 to 14.1 years, n = 97) compared to dogs with spontaneous eunatraemic eukalaemic hypoadrenocorticism (median age: 8.3, range: 3.0 to 12.7 years, n = 26). Sixty-six dogs were included in the survival analysis. For dogs with spontaneous hyponatraemic and/or hyperkalaemic hypoadrenocorticism, all of which were managed with desoxycorticosterone pivalate, median survival time was 5.7 years (95% CI: 4.0 to 7.2 years; n = 47) and median age at death was 11.0 years (range: 4.0 to 17.0 years; n = 30). For dogs with spontaneous eunatraemic eukalaemic hypoadrenocorticism, median survival time was 5.6 years (95% CI: 4.1-N/A years; n = 9) and median age at death was 11.8 years (range: 11.0 to 13.0 years; n = 4). The majority of owners that completed the questionnaire reported side effects commonly associated with glucocorticoid therapy.

CLINICAL SIGNIFICANCE

Hypoadrenocorticism carries an excellent prognosis. Desoxycorticosterone pivalate was the most frequently used mineralocorticoid therapy in this group of dogs.

Comparison of prednisolone and alternative glucocorticoid dosing protocols for canine hypoadrenocorticism: insights from a survey-based study

Objectives

The aim of the study was to analyze glucocorticoid (GC) dosing protocols in dogs with hypoadrenocorticism (HA), and to identify predictors for optimal clinical outcomes during both the acute and chronic phases of the disease, as well as during long-term therapy.

Methods

This observational cross-sectional study utilized a case-based online questionnaire. Practicing veterinarians across Germany were invited to participate. The survey collected data in the disease course and follow-ups. Responses were analyzed using descriptive statistics, single and multiple comparisons, and a multivariable logistic regression model.

Results

For 103 dogs the questionnaire was fully completed and analyzed. Of these, 85 dogs (82.5%) were hospitalized, and they received either prednisolone (52.9%), dexamethasone (31.8%) or hydrocortisone (11.8%). Hydrocortisone therapy was associated with a shorter hospitalization time and faster normalization of electrolytes compared to prednisolone. Follow-up data were available for 85 dogs, with 82.35% (n = 70/85) achieving an optimal or well-adjusted clinical outcome. Multivariable logistic regression analysis indicated that the eukalemic and eunatremic form was significantly less associated with the presence of azotemia and the occurrence of an acute adrenal crisis. Dividing the daily GC dosage was associated with poorer clinical outcomes and a reduced likelihood of achieving optimal medication adjustment.

Conclusion

Our findings provide new, relevant recommendations for the therapeutic management of HA in dogs. Hydrocortisone appears to be a promising treatment for managing HA during hospitalization, highlighting its potential use in clinical practice. Once-daily administration of prednisolone is advisable for long-term therapy. To achieve the best possible outcome, implementing an optimal treatment protocol is essential, which veterinarians should tailor based on the needs of both owners and animals. The main limitations of the study include its retrospective nature and the limited number of participants. Future studies, particularly prospective ones, could further validate the beneficial effects of hydrocortisone and evaluate long-term therapy in comparison to prednisolone.

Development of mass spectrometric methods for determination of desoxycorticosterone pivalate and its esterase product in canine serum

Hypoadrenocorticism is a serious condition in dogs that results from autoimmune adrenalitis and depletion of mineralocorticoids and glucocorticoids. Affected dogs respond well to glucocorticoid supplementation and treatment with the synthetic mineralocorticoid desoxycorticosterone pivalate (DOCP). DOCP injected once monthly resolves serum Na/K abnormalities and normalizes water balance, but therapy is expensive. Cost abatement involves prolongation of the 30-day dosage interval or decreasing the 2.2 mg/kg dosage. These approaches are not based on DOCP pharmacokinetics. A full assessment of the practicality of either approach would benefit from understanding drug pharmacokinetics, requiring measurement of DOCP and its esterase product desoxycorticosterone (DOC) in canine serum while avoiding toxic endpoints from overdosing. Mass spectrometric methods were developed including gas chromatography-tandem mass spectrometry of DOCP and DOC-methoxime trimethylsilyl derivatives, an approach sensitive to 2 ng/mL. Greater sensitivity was desired, so liquid chromatography-tandem mass spectrometry (LC-MS/MS) with ESI+ ionization was investigated. Supported liquid extraction was devised for serum with recoveries ∼100%. The LC-MS/MS method was validated for linearity, precision, accuracy and limits of detection (0.029 and 0.019 ng/mL for DOC and DOCP, respectively). A pilot experiment with DOCP-treated hypoadrenocorticism dogs over one-month revealed DOC baseline values as 0.183+/-0.090 ng/mL, which increased to the 1.0 - 2.2 ng/mL range. DOCP was not visible in any samples suggesting 100% conversion. Halving the dosage to 1.1 mg/kg still showed clear increases over the DOC baseline. MS fragmentation involved ring cleavages, dehydrations and double-charged fragments. The methodology was robust and suitable for studying DOC/DOCP pharmacokinetics in future studies of hypoadrenocorticism dogs.

Clinical features and long-term management of cats with primary hypoadrenocorticism using desoxycorticosterone pivalate and prednisolone

BACKGROUND

Primary hypoadrenocorticism (PH) is rare in cats and knowledge about treatment is sparse.

OBJECTIVE

To describe cats with PH with a focus on long-term treatment.

ANIMALS

Eleven cats with naturally occurring PH.

METHODS

Descriptive case series with data on signalment, clinicopathological findings, adrenal width, and doses of desoxycorticosterone pivalate (DOCP) and prednisolone during a follow-up period of >12 months.

RESULTS

Cats ranged from 2 to 10 years (median 6.5); 6 cats were British Shorthair. Most common signs were reduced general condition and lethargy, anorexia, dehydration, obstipation, weakness, weight loss, and hypothermia. Adrenal glands on ultrasonography were judged small in 6. Eight cats could be followed for 14 to 70 months (median: 28). Two were started on DOCP doses ≥2.2 mg/kg (2.2; 2.5) and 6 < 2.2 mg/kg (1.5-2.0 mg/kg, median 1.8) q28 days. Both high-dose cats and 4 low-dose cats needed a dose increase. Desoxycorticosterone pivalate and prednisolone doses at the end of the follow-up period were 1.3 to 3.0 mg/kg (median: 2.3) and 0.08 to 0.5 mg/kg/day (median: 0.3), respectively.

CONCLUSIONS AND CLINICAL IMPORTANCE

Desoxycorticosterone pivalate and prednisolone requirements in cats were higher than what is currently used in dogs; thus, a DOCP starting dose of 2.2 mg/kg q28 days and a prednisolone maintenance dose of 0.3 mg/kg/day titrated to the individual need seems warranted. Small adrenal glands (width < 2.7 mm) on ultrasonography in a cat suspected of hypoadrenocorticism can be suggestive of the disease. The apparent predilection of British Shorthaired cats for PH should be further evaluated.

Use of Deoxycorticosterone Pivalate by Veterinarians: A Western European Survey

This study aims to gather knowledge about the use of deoxycorticosterone pivalate (DOCP) by Western European Veterinarians (WEV) in dogs with typical hypoadrenocorticism. An observational cross-sectional study was conducted using an online survey, translated into four languages and disseminated to veterinary affiliates and mailing lists in six countries of Western Continental Europe. Respondents were tasked to share their therapeutic approach to hypoadrenocorticism, whether they preferred DOCP or fludrocortisone and the specific practical use of DOCP. One-hundred and eighty-four responses were included. Of these, 79.9% indicated that they preferred prescribing DOCP over fludrocortisone as a first-line treatment for mineralocorticoid supplementation. A total of 154 respondents had used DOCP at least once. Eighty percent of those who reported their initial dosage prescribed 2.2 mg/kg. After starting DOCP, 68.2% of the respondents assess electrolytes 10 and 25 days after administration following manufacturer instructions. In stable dogs, electrolytes are monitored quarterly, monthly, semi-annually, and annually by 44.2%, 34.4%, 16.9%, and 4.6% of respondents respectively. When treatment adjustment is required, 53% prefer to reduce dosage while 47% increase the interval between doses. Overall, DOCP is the preferred mineralocorticoid supplementation among WEV. Reported variability underlies the need to investigate the best strategies for DOCP use and therapeutic adjustments.

Low-dose desoxycorticosterone pivalate treatment of hypoadrenocorticism in dogs: A randomized controlled clinical trial

Background

Desoxycorticosterone pivalate (DOCP) is a commonly used mineralocorticoid replacement for dogs with primary hypoadrenocorticism (HA), but manufacturer‐recommended dosing protocols can be cost‐prohibitive. Recent reports also have raised concerns that label dose protocols could be excessive.

Objective

To investigate the relative efficacy and adverse effects of 2 DOCP dosages in dogs with primary glucocorticoid and mineralocorticoid deficient HA.

Animals

Thirty‐seven dogs, including 19 test population dogs and 18 controls.

Methods

Randomized controlled double‐blinded clinical trial. Dogs with newly diagnosed primary HA were assigned to standard (2.2 mg/kg q30d, control population) or low‐dose (1.1 mg/kg q30d, test population) DOCP treatment. Clinical and laboratory variables were assessed 10 to 14 days and approximately 30 days after each DOCP treatment for 90 days.

Results

Mean serum sodium to potassium ratios at reevaluations were ≥32 in both populations throughout the study. No dog developed electrolyte abnormalities warranting medical treatment, although hypokalemia occurred on at least 1 occasion in 9 controls and 6 test population dogs. Urine specific gravities (median, interquartile range) were lower in control dogs (1.022, 1.016‐1.029) as compared to test population dogs (1.033, 1.023‐1.039; P = .006). Plasma renin activity was overly suppressed on 84 of 104 (80.8%) assessments in control dogs whereas increased renin activity occurred on 23 of 112 (20.5%) assessments in test population dogs.

Conclusions and Clinical Importance

Low‐dose DOCP protocols appear to be safe and effective for treatment of HA in most dogs. Standard‐dose protocols are more likely to result in biochemical evidence of overtreatment.

Evaluation of a low-dose desoxycorticosterone pivalate treatment protocol for long-term management of dogs with primary hypoadrenocorticism

Background

Lowering the dose of desoxycorticosterone pivalate (DOCP) for the treatment of dogs with primary hypoadrenocorticism (PH) decreases costs and could lead to increased owner motivation to treat their affected dogs.

Objective

To evaluate the efficacy of a low‐dose DOCP treatment protocol in dogs with PH.

Animals

Prospective study, 17 client‐owned dogs with naturally occurring PH (12 newly diagnosed, 5 previously treated with fludrocortisone acetate [FC]).

Methods

Dogs with newly diagnosed PH were started on 1.5 mg/kg DOCP SC; dogs previously treated with FC were started on 1.0‐1.8 mg/kg DOCP SC. Reevaluations took place at regular intervals for a minimum of 3 months and included clinical examination and determination of serum sodium and potassium concentrations. The DOCP dosage was adjusted to obtain an injection interval of 28‐30 days and to keep serum electrolyte concentrations within the reference interval.

Results

Median (range) follow‐up was 16.2 months (4.5‐32.3 months). The starting dosage was sufficient in all but 2 dogs and had to be significantly decreased after 2‐3 months to a median dosage (range) of 1.1 mg/kg (0.7‐1.8). Dogs 3 years of age or younger needed significantly higher dosages compared to older dogs. None of them, however, needed the 2.2 mg/kg DOCP dosage, recommended by the manufacturer.

Conclusions and Clinical Importance

A starting dosage of 1.5 mg/kg DOCP is effective in controlling clinical signs and serum electrolyte concentrations in the majority of dogs with PH. An additional dose reduction often is needed to maintain an injection interval of 28‐30 days. Young and growing animals seem to need higher dosages.