WHAT IS THIS MEDICINE AND WHAT IS IT USED FOR?
Ramiven contains abemaciclib, a targeted cancer medicine that works by
blocking two proteins — CDK4 and CDK6 (cyclin-dependent kinases 4 and 6) — that
cancer cells need to pass through the growth cycle and divide. By putting the
brakes on this process, abemaciclib slows or stops the growth of breast cancer
cells.
It is similar in class to palbociclib (entries 136/137) but has some
important differences: it is taken twice daily (not once daily), it is given
continuously without a planned week off, and it has a notably higher rate of
diarrhoea. Abemaciclib is approved for hormone receptor-positive (HR+),
HER2-negative advanced or metastatic breast cancer — in combination with a
hormonal medicine (an aromatase inhibitor such as letrozole or anastrozole, or
fulvestrant).
It is also approved in the early breast cancer setting (as adjuvant
therapy after surgery) for high-risk early HR+/HER2- breast cancer, in
combination with endocrine therapy.
3. HOW TO TAKE THIS MEDICINE
The standard dose is 150mg twice daily — taken approximately 12 hours
apart, every day without a week off. For example: one tablet at 8am and one
tablet at 8pm. The 14-tablet pack provides a one-week supply at this
twice-daily schedule.
Take with or without food. Swallow tablets whole. If significant side
effects (particularly diarrhoea or low blood counts) occur, your oncologist may
reduce the dose to 100mg twice daily, then 50mg twice daily. If you vomit after
taking a dose, do not take another — wait for the next scheduled dose.
Unlike palbociclib (which has a 3-week-on, 1-week-off schedule),
abemaciclib is taken every day without a break. This continuous dosing is an
important difference — do not take a week off unless specifically instructed by
your oncologist. Always take alongside your co-prescribed hormonal medicine
(aromatase inhibitor or fulvestrant).
⚠ PATIENT TIP: Diarrhoea is the most common side
effect of abemaciclib — it affects the majority of patients, often in the first
few weeks. Your oncologist will usually prescribe an anti-diarrheal medicine
(loperamide) to take at the first sign of loose stools. Start loperamide
promptly — do not wait until diarrhoea is severe. Stay well hydrated. Most
patients find diarrhoea improves significantly after the first month.
4. POSSIBLE SIDE EFFECTS
|
How Common? |
Side Effects |
|
Very Common |
Diarrhoea (most common
— affects over 80% of patients, usually worst in first month), neutropenia
(low white blood cells — increasing infection risk), fatigue, nausea,
anaemia, infections (urinary tract, upper respiratory), abdominal pain,
decreased appetite, vomiting, headache, hair thinning |
|
Common |
Low platelet count,
raised liver enzymes, dehydration, dizziness, rash, dry skin, mouth sores |
|
Serious — Seek Urgent
Medical Help |
Febrile neutropenia:
fever above 38°C with low blood counts — go to hospital immediately. Severe
or persistent diarrhoea (Grade 3: 7+ loose stools per day above baseline, or
that prevents daily activities) — contact oncology team same day. Pulmonary
embolism (blood clot in lung): sudden breathlessness, chest pain, rapid heart
rate. Hepatotoxicity: jaundice, dark urine, severe right-sided abdominal
pain. Interstitial lung disease: new persistent dry cough or worsening
breathlessness. |
5. WHO SHOULD NOT TAKE THIS MEDICINE
Abemaciclib should not be used with strong CYP3A4 inhibitors or inducers
(see interactions). It must not be taken during pregnancy — effective
contraception is essential. Use with caution in significant liver or kidney
impairment. Tell your oncologist about all medicines, supplements, and herbal
products you take.
⚠ DIARRHOEA MANAGEMENT IS CRITICAL: Diarrhoea
from abemaciclib can rapidly lead to dehydration, electrolyte imbalances, and
hospitalisation if not managed promptly. Start loperamide at the first sign of
loose stools — do not wait. Drink extra fluids. Report severe diarrhoea (7 or
more loose stools daily, or diarrhoea with fever or dehydration) to your
oncology team immediately. This is the leading reason for dose reduction.
⚠ BLOOD COUNT MONITORING: Neutropenia is common.
Full blood counts are checked before treatment, before each monthly cycle, and
at day 15 of the first two cycles. If you develop a fever above 38°C at any
time, go to hospital immediately — do not wait.
⚠ CONTINUOUS DOSING — NO PLANNED BREAK:
Abemaciclib is taken every day without a week off. This is different from
palbociclib. Do not stop for a week unless your oncologist specifically
instructs you to.
6. MEDICINES THAT INTERACT WITH THIS TREATMENT
Strong CYP3A4 inhibitors (ketoconazole, clarithromycin, ritonavir,
grapefruit juice) dramatically increase abemaciclib levels — avoid these
combinations. Strong CYP3A4 inducers (rifampicin, phenytoin, carbamazepine, St.
John's Wort) significantly reduce abemaciclib levels, risking treatment failure
— avoid.
Grapefruit and grapefruit juice must be avoided. Abemaciclib slightly
inhibits creatinine secretion in the kidneys — it can cause modest rises in
serum creatinine without indicating true kidney damage; confirm with your
oncologist if concerned.
7. HOW TO STORE THIS MEDICINE
Store below 25°C. Keep in original packaging away from moisture and
light. Keep out of reach of children.
8. PRESCRIPTION REQUIREMENT
|
Field |
Details |
|
Status |
Prescription Only
Medicine (POM) — Specialist (oncology) prescription required |
9. GUIDANCE FOR PATIENTS & CAREGIVERS
Take one tablet in the morning and one in the evening, every day without
a week off — this is different from some similar medicines. Always take
alongside your aromatase inhibitor or fulvestrant as prescribed.
Start loperamide at the very first sign of loose stools — keeping it on
hand before you need it is important. Drink plenty of fluids throughout
treatment. Attend all blood test appointments. If you develop a fever above
38°C, go to hospital immediately.
Avoid grapefruit. Use effective contraception throughout treatment. Tell
all healthcare providers you are taking abemaciclib before they prescribe
anything new.
10. PHARMACIST & PRESCRIBER NOTES
|
Field |
Details |
|
Clinical Dispensing
Notes |
CDK4/6 inhibitor —
continuous twice-daily dosing (no 7-day break — key difference from
palbociclib). Confirm co-prescription of hormonal partner medicine (AI or
fulvestrant). Diarrhoea management counselling is essential at every
dispensing: prescribe or recommend loperamide prophylactically; instruct
patient to start at first loose stool. Grade 3+ diarrhoea (≥7 stools/day
above baseline) requires dose interruption and oncologist contact same day.
FBC monitoring: pre-treatment, before monthly cycles, day 15 of cycles 1 and
2. Febrile neutropenia emergency protocol (fever >38°C = immediate
hospital). CYP3A4 inhibitor/inducer interactions — grapefruit avoidance.
Creatinine rise (may be pharmacological, not nephrotoxic — check cystatin C
if concerned). Embryo-fetal toxicity: contraception during and 3 weeks
(women) / 3 months (men) post-treatment. LFT monitoring per oncologist
schedule. ILD monitoring — persistent new cough or breathlessness requires
oncology review. |
11. FREQUENTLY ASKED QUESTIONS
Q: Why is diarrhoea so common and what do I do about it?
Abemaciclib affects the cells lining the gut as well as cancer cells,
causing diarrhoea in the majority of patients — especially in the first 4 to 8
weeks of treatment. The key is to act quickly: start loperamide (Imodium) at
the first sign of loose stools — do not wait until it is severe. Drink extra
fluids. Most patients find the diarrhoea improves significantly after the first
month.
Q: Do I take it every day including weekends?
Yes — abemaciclib is a continuous daily treatment with no planned breaks,
unlike palbociclib. Take it every single day, 12 hours apart. Only pause
treatment if your oncologist specifically instructs you to.
Q: Can I eat grapefruit?
No — grapefruit and grapefruit juice must be avoided throughout
treatment. They block an enzyme that breaks down abemaciclib, causing blood
levels to rise dangerously.
Q: Do I need contraception?
Yes — abemaciclib can harm an unborn baby. Women should use effective
contraception during treatment and for 3 weeks after the last dose. Men should
use contraception for 3 months after the last dose.