DRUG NAMEMITOTANE

:

SYNONYM(S):

o,p'-DDD

COMMON TRADE NAME(S):

LYSODREN(r)

CLASSIFICATION

:

Miscellaneous

Special pediatric considerations are noted when applicable, otherwise adult provisions apply.

MECHANISM OF ACTION

:

[1]

Mitotane is a derivative of the insecticide DDT and causes direct necrosis and atrophy of the adrenal cortex.

PHARMACOKINETICS

:

[2,3,4,5,6,7,8]

Oral Absorption 40%
Distribution found in all body tissues, but primarily in fat
cross blood brain barrier? mitotane: no; metabolite: trace
Vd no information found
PPB no information found
Metabolism both liver and kidney metabolize small portions
active metabolite(s) no information found
inactive metabolite(s) yes
Excretion 60% excreted unchanged in feces; small portion excreted in bile as metabolites
urine 10-25% as metabolites
t1/2 18-159 days
Cl no information found

USES

:

[9]

Adrenal cortical cancer Health Protection Branch approved indication.

SPECIAL PRECAUTIONS

:

[9]

Cancer Drug Manual September 1994

Mitotane

The mutagenic, carcinogenic and teratogenic effects of mitotane are not known. Its safe use in pregnancy and its effects on fertility have not been established. Breast feeding is not recommended due to the potential secretion into breast milk.

SIDE EFFECTS

:

[9,10,11,12]

ORGAN SITE SIDE EFFECT ONSET
cardiovascular hypertension (rare) E
orthostatic hypotension (rare) E
central nervous system lethargy (25%) E D
dizziness (15%) E D
endocrine adrenal insufficiency E
gastrointestinal nausea and vomiting I
diarrhea E
anorexia E
hypersensitivity allergic skin rash (15%, transient) E
ocular blurred vision, double vision (rare) E
toxic retinopathy (rare) E
cataracts (rare) E D
renal/metabolic hematuria, hemorrhagic cystitis (rare) D
albuminuria (rare) D
other minor aches (rare) E
fever (rare) E

Dose-limiting side effects are underlined. I = immediate (onset in hours to days); E = early (days to weeks); D = delayed (weeks to months); L = late (months to years) Mitotane's main action is adrenocortical suppression. Supplementation with exogenous steroids is necessary (eg, prednisone 5 mg qam and 2.5 mg qpm or cortisone acetate 25 mg qam and 12.5 mg qpm). Occasional patients will require fludrocortisone (FLORINEF(r)) 0.1 mg po daily for mineralocorticoid deficiency causing orthostatic hypotension. If shock, severe trauma or infection occurs, mitotane should be temporarily discontinued and steroids immediately given. When mitotane is discontinued, the steroid should be tapered slowly, but may need to be continued indefinitely. Patients should use a medical alert tag or bracelet warning of adrenal suppression.

Gastrointestinal toxicity

occurs in 80% of patients.

Adverse CNS effects

occur in 40% of patients and are manifested as lethargy, somnolence, dizziness, depression, irritability, confusion and tremors. More rare CNS side effects, consisting of speech difficulty,

Cancer Drug Manual September 1994

memory loss, ataxia and halllucinations, have been reported. Long-term use can cause brain damage. Behavioral and neurological assessments should be performed periodically when continuous mitotane exceeds 2 years.

INTERACTIONS

:

[4,13,14]

AGENT EFFECT MECHANISM MANAGEMENT
measurement of urinary adrenal steroids false negative for cortisol secretion rate mitotane increases extra-adrenal metabolism of cortisol so less is excreted in urine obtain both urine and plasma levels of cortisol
barbiturates, phenytoin increased metabolism of these drugs mitotane induces hepatic microsomal enzyme oxidation system monitor pharmacological effects; adjust dose of barbiturate or phenytoin prn
CNS depressants enhanced CNS depression additive caution
spironolactone blocks effect of mitotane uncertain avoid
thyroid function test decrease in serum protein-bound iodine mitotane binds thyroxine-binding globulin Resin triodothyronine uptake tests are not affected. Free thyroxine concentrations apparently remain in the normal range.
warfarin decreased pharmacological response to warfarin enhanced metabolism of warfarin by hepatic microsomal enzyme oxidation system monitor prothrombin times and adjust warfarin dose prn whenever mitotane is stopped or started

SUPPLY AND STORAGE

: [9]

Tablets:

500 mg; store at room temperature.

DOSAGE GUIDELINES

:

[2,4,8,15]

Cancer Drug Manual September 1994

Mitotane

Refer to protocol by which patient is being treated.

Adults:

Oral

: not to be taken with a fatty meal

daily: start 500 mg qid, escalate by 1000 mg/day every 1-2 weeks to maximum tolerated dose

Maximum tolerated dose:

usual: 8-10 g/day (range 2-19 g)

Adequate trial

: 3 months at maximum tolerated dose (10% of patients with measurable

response required >3 months).

Adrenal replacement:

Should be given with steroids - eg, prednisone 5 mg qam and 2.5 mg qpm or

cortisone acetate 25 mg qam and 12.5 mg qpm. Occasional patients will require fludrocortisone (FLORINEF(r)) 0.1 mg daily for mineralocorticoid deficiency causing orthostatic hypotension. If shock, severe trauma or infection occurs mitotane should be temporarily discontinued and steroids immediately given. When mitotane is discontinued, the steroid should be tapered slowly, but may need to be continued indefinitely. Patients should use medical alert tag or bracelet warning of adrenal suppression.

Dosage in myelosuppression:

no adjustment required

Dosage in renal failure:

adjustment required, no details found

Dosage in hepatic failure:

adjustment required, no details found

Children:

Oral

: daily: (2-8 year olds) 0.5-1 g, escalate to 1-4 g/day

Cancer Drug Manual September 1994

MITOTANE FACT SHEET

FOR THE HEALTH CARE PROFESSIONAL

OTHER NAMES o,p'-DDD, LYSODREN(r)
USES * HPB approved adrenal cortical cancer *
DOSAGE FORMS oral tablet: 500 mg (not to be taken with a fatty meal)
USUAL DOSE RANGE Adults: initial: 500 mg po qid, escalate by 1000 mg/day q1-2w to maximum tolerated dose usual: 8-10 g/day divided range: 2-19 g/day divided adequate trial: 3 months at maximum tolerated dose Children: (2-8 year olds) 0.5-1 g po daily, escalate to 1-4 g/day
DOSE REDUCTIONS liver (hepatic) failure kidney (renal) failure central nervous system toxicity
ONSET SIDE EFFECT * may be life-threatening side effects in bold, italic type are common
IMMEDIATE (hours to days) nausea and vomiting
EARLY (days to weeks) * adrenal insufficiency (glucocorticoid and sometimes mineralocorticoid replacement required) gastrointestinal problems ( anorexia , diarrhea) central nervous system problems (40%, lethargy 25%, dizziness 15%, depression, irritability, confusion, tremors) skin problems (transient rash 15-20%) minor aches (rare) fever (rare) blood pressure problems (hypertension, orthostatic hypotension) eye problems (blurred or double vision, toxic retinopathy, cataracts)
DELAYED/LATE (weeks to years) central nervous system problems eye problems (cataracts) bladder problems (hematuria, hemorrhagic cystitis, albuminuria)

CONTRAINDICATIONS

known hypersensitivity to mitotane

pregnancy and breast feeding

Cancer Drug Manual September 1994

Mitotane

SIGNIFICANT INTERACTIONS *increases toxicity barbiturates, *CNS depressants, phenytoin (DILANTIN(r)), spironolactone (ALDACTONE(r)), warfarin (COUMADIN(r))
MONITORING periodically: mitotane levels, electrolytes, DHEAS (dihydroepiandrostenedione), liver function, kidney function, blood pressure, neurological assessment (>2 years treatment)

TEACHING AIDS * For the Patient: Mitotane

NOTES:

* Glucocorticoid replacement (eg, prednisone 5 mg po qam and 2.5 mg po qpm or cortisone acetate 25 mg po qam and 12.5 mg qpm) is required to avoid an adrenal crisis.

Cancer Drug Manual September 1994

FOR THE PATIENT

Mitotane :

Other names: LYSODREN(r)

Cancer Drug Manual September 1994

Mitotane

SIDE EFFECTS MANAGEMENT
You may feel drowsy and/or dizzy when you take mitotane. *Do not drive a car or operate machinery if you are feeling drowsy, dizzy or less alert than usual. *Avoid alcohol as it may make you more drowsy or dizzy.
Nausea (upset stomach) may occur. *Take your mitotane after eating. *Eat often in small amounts. *Try the ideas in For the Patient: Nausea . *You may be given an antinausea drug to take at home. It is easier to prevent nausea than treat it once it has occurred, so follow directions closely. Most antinausea drugs cause drowsiness.
A skin rash may occur. This should go away in a week or two even though you keep taking mitotane. *Keep on taking your mitotane. *Take an antihistamine such as diphenhydramine (eg, Benadryl) 25 mg capsules 2-4 times a day when needed. Most antihistamines cause drowsiness.
Your body's ability to handle illness or injury is weakened by mitotane. You may need extra steroids to help you get better. *Check with your doctor if you have an infection, illness or injury.

SEE YOUR DOCTOR AS SOON AS POSSIBLE (DURING OFFICE HOURS) IF YOU HAVE:

CHECK WITH YOUR DOCTOR IF ANY OF THE FOLLOWING CONTINUE OR BOTHER YOU:

Uncontrolled nausea, vomiting, loss of appetite or diarrhea.

Mental depression.

Dizziness or drowsiness that does not improve.

Skin rash that lasts longer than 2 weeks, gets worse or is unbearable.

REPORT ADDITIONAL PROBLEMS TO YOUR DOCTOR.

Notes:

Cancer Drug Manual September 1994

BIBLIOGRAPHY

:

  1. Haskell CM, ed. Cancer treatment, 3rd ed. Philadelphia: WB Saunders Co, 1990.

  2. Kastrup EK et al, eds. Facts and comparisons: Loose-leaf information service. St. Louis: JB Lippincott Co, 1993:688a-b.

  3. Dorr RT, Fritz WL, eds. Cancer chemotherapy handbook. New York: Elsevier Science Publishing Co Inc, 1980.

  4. McEvoy GK, ed. American hospital formulary service: Drug information 1993. Bethesda: American Society of Hospital Pharmacists, 1994:672.

  5. Pinedo HM, Chabner BA, eds. Cancer chemotherapy/7: The EORTC cancer chemotherapy annual. New York: Elsevier Science Publishing Co Inc, 1985:345.

  6. Molenaar AJ, Van Sters AP. O,p'-DDD values in plasma and tissue during and after chemotherapy of adrenocortical carcinoma (Abstract). Acta Endocr Suppl 1975; 199:226.

  7. Dorr RT, Von Hoff DD. Cancer chemotherapy handbook, 2nd ed. Norwalk: Appleton & Lange, 1994:726-9.

  8. Lyss AP. Enzymes and random synthetics. In: Perry MC, ed. The chemotherapy source book. Baltimore: Williams & Wilkins, 1992:403-4.

  9. Krogh CME, ed. Compendium of pharmaceuticals and specialties, 28th ed. Ottawa: Canadian Pharmaceutical Association, 1993.

  10. Gutierrez ML, Crooke ST. Mitotane (o,p'-DDD). Cancer Treat Rev 1980; 7:49-55.

  11. Samaan NA, Hickey CR. Adrenal cortical carcinoma. Semin Oncol 1987; 14:292-6.

  12. Boven E, Vermorken JB, Van Slooten H, et al. Complete response of metastasized adrenal cortical carcinoma with o,p'-DDD: Case report and literature review. Cancer 1984; 53:26-9.

  13. Tatro DS, ed. Drug interaction facts. St. Louis: Facts and Comparisons, 1992:580.

  14. Hansten PD, Horn JR, eds. Drug interactions and updates. Vancouver, WA: Applied Therapeutics Inc, 1992:314.

  15. Wittes RE, ed. Manual of oncologic therapeutics 1991-1992. Philadelphia: JB Lippincott Co, 1991:111-2.

  16. USP DI Volume I: Drug information for the health care professional, 14th ed. Rockville: United States Pharmacopeial Convention Inc, 1994:1937-9.

  17. USP DI Volume II: Advice for the patient: Drug information in lay language, 14th ed. Rockville: United States Pharmacopeial Convention Inc, 1994:934-6.

Cancer Drug Manual September 1994