2 - Topical and Intralesional Antiviral Agents Flashcards Preview

Derm Pharm > 2 - Topical and Intralesional Antiviral Agents > Flashcards

Flashcards in 2 - Topical and Intralesional Antiviral Agents Deck (114)
Loading flashcards...
1
Q

Topical and intralesional agents can be:

(1) viricidal
(2) immune-enhancing
(3) cytodestructive

A

True

2
Q

The topical viricidal agents include:

(1) acyclovir
(2) penciclovir
(3) cidofovir
(4) foscarnet
(5) idoxuridine

A

True

3
Q

The topical/intralesional immune enhancers include:

(1) topical imiquimod
(2) topical and intralesional interferon

A

True

4
Q

The topical/intralesional cytodestructive agents include:

(1) intralesional bleomycin
(2) topical podophyllin/podofilox
(3) topical trichloroacetic acid
(4) topical cantharidin
(5) topical salicylic acid
(6) topical 5-fluorouracil

A

True

5
Q

Topical acyclovir 5% cream and ointment are FDA approved for the treatment of HSV

A

True

6
Q

Even when acyclovir is applied topically to damaged skin including localised VZV infection, systemic absorption is limited

A

True

7
Q

Topical acyclovir is specific for HSV-infected cells because the drug requires phosphorylation by the viral enzyme thymidine kinase

A

True

8
Q

Topical acyclovir is most effective against HSV-1 and HSV-2 and less effective against VZV due to less efficient phosphorylation by the VZV viral thymidine kinase

A

True

9
Q

Topical acyclovir is not effective against CMV because CMV does not encode for thymidine kinase

A

True (acyclovir needs to be phosphorylated by viral thymidine kinase to be able to be incorporated into viral DNA by viral-DNA polymerase)

10
Q

Topical acyclovir 5% ointment is approved of the management of initial genital HSV in immunocompetent patients

A

True (early application within 24 hours of onset of prodrome is important)
Initial = every 3 hours up to 6 X daily for 7 days
Recurrent = 5 X daily for 4 days
A finger cot or rubber glove should be used when applying the medication to prevent autoinoculation or transmission to other persons

11
Q

Topical acyclovir 5% ointment/cream is approved of the management of limited non-life threatening mucocutaneous genital HSV and HSV labialis in immunocompetent patients

A

True (early application within 24 hours of onset of prodrome is important)

12
Q

Topical acyclovir may cause application site reactions including mild pain and burning, although placebo patients experienced similar adverse effects

A

True

13
Q

Both topical acyclovir and penciclovir are classified as pregnancy category B

A

True

14
Q

Topical cidofovir and foscarnet are classified as pregnancy category C

A

True (listed for the injectable version of the drug)

15
Q

Topical acyclovir has limited use as monotherapy for genital HSV and HSV labialis and when medically tolerable, oral acyclovir is preferred over topical acyclovir for recurrent genital herpes given the greater efficacy in reducing the duration of viral shedding and time to crusting and healing of lesions

A

True

16
Q

Penciclovir is only available in topical preparation because of poor oral availability

A

True (Famciclovir, the prodrug of penciclovir is available in oral form)

17
Q

Penciclovir is selectively phosphorylated to the monophosphate from by viral thymidine kinase, and then further phosphorylated by human cellular kinases to the active triphosphate for, which inhibits viral replication by competitively binding to viral DNA polymerase

A

True

18
Q

Even though acyclovir and penciclovir are qualitatively similar (with similar mode of action), penciclovir exhibits more efficient phosphorylation, a higher affinity to viral DNA polymerase, and increased stability of its active triphosphate form; thus leading to longer duration of activity

A

True

19
Q

Penciclovir exhibits inhibitory activity against HSV-1, HSV-2, VZV and EBV

A

True (limited activity against CMV)

20
Q

Penciclovir exhibits limited in vitro inhibitory activity against CMV

A

True

21
Q

Penciclovir 1% cream is indicated for the treatment of recurrent HSV labialis in immunocompetent individuals 12 years and older

A

True (Penciclovir 1% cream should be applied at the earliest sign/symptom to all lesions every 2 hours/at least 6X daily for 4 days)

22
Q

Penciclovir 1% cream reduced pain and viral shedding associated with HSV labialis independent of the timing of medication initiation

A

True

23
Q

The most frequently reported adverse effect with topical Penciclovir is headache

A

True

24
Q

Given the inconvenience or frequent application of topical Penciclovir (every 2 hours, or at least 6X daily), the expense and the reduction of symptoms of viral shedding by half a day; the clinical benefit of penciclovir over oral antiviral therapy is limited

A

True

25
Q

If oral therapy is contraindicated or not available, topical Penciclovir is an alternative option to topical acyclovir for HSV labialis

A

True (although no head to head studies performed between these 2)

26
Q

Cidofovir is an acyclic nucleotide that exhibits antiviral activity against a broad range of DNA viruses including HPV, human herpes viruses, and some pox viruses

A

True

27
Q

IV Cidofovir is used to treat CMV retinitis in AIDS patients

A

True

28
Q

No oral preparations of cidofovir are available, however cidofovir has been compounded in topical formulations for verruca vulgaris (HPV)

A

True (reported anecdotally or in small studies including children with recalcitrant disease)

29
Q

Unlike acyclovir and penciclovir, cidofovir does not depend on thymidine kinase for its phosphorylation

A

True

30
Q

Cidofovir acts as a competitive inhibitor for incorporation into viral DNA by viral DNA polymerase and blocks viral DNA synthesis

A

True

31
Q

No oral preparations of cidofovir are available, however cidofovir has been compounded in topical formulations for condyloma acuminata/genital warts (HPV)

A

True (reported anecdotally or in small studies in immunocompetent patients)

32
Q

No oral preparations of cidofovir are available, however cidofovir has been compounded in topical formulations for herpes simplex (HSV)

A

True (reported anecdotally or in small studies in AIDS patients with acyclovir-resistant HSV as well as immunocompetent patients)

33
Q

No oral preparations of cidofovir are available, however cidofovir has been compounded in topical formulations for orf (parapox virus)

A

True (reported anecdotally or in small studies)

34
Q

No oral preparations of cidofovir are available, however cidofovir has been compounded in topical formulations for molluscum contagiosum (pox virus)

A

True (reported anecdotally or in small studies in children and adults with HIV with recalcitrant disease)

35
Q

Topical cidofovir may cause headaches, nausea, and pharyngitis, though with similar frequency to placebo

A

True

36
Q

Application site pruritus, rash, pain, paraesthesia and ulceration are increased with higher concentrations of topical cidofovir

A

True

37
Q

Foscarnet is a pyrophosphate (not a nucleoside) analog with activity against all herpes viruses

A

True

38
Q

Foscarnet is used in the treatment of CMV infection in immunocompromised patients

A

True

39
Q

Foscarnet is the oral drug of choice for acyclovir-resistant HSV

A

True (does not require activation by either cellular or viral enzymes)

40
Q

Foscarnet does not require activation by either cellular or viral enzymes

A

True (drug of choice for acyclovir-resistant HSV)

NB. Acyclovir relies on viral thymidine kinase for phosphorylation and subsequent inhibition of viral replication

41
Q

Foscarnet is not a nucleoside analog, and so nucleoside-resistant viral DNA polymerase are susceptible/sensitive to Foscarnet

A

True (foscarnet is a pyrophosphate analog instead)
NB. Acyclovir and Penciclovir are nucleoside analogs (Valacyclovir is the prodrug or acyclovir and Famciclovir is the prodrug of Penciclovir)

42
Q

Idoxuridine is a thymidine analog which has limited efficacy in genital HSV, HSV labialis, and VZV infections

A

True (only available as an ophthalmic solution for the treatment of herpes keratitis)

43
Q

Idoxuridine is only available as an ophthalmic solution for the treatment of herpes keratitis

A

True (has limited efficacy in genital HSV, HSV labialis, and VZV infections)

44
Q

Imiquimod is a topical immunomodulating agent approved by the FDA for treatment of external genital and perianal warts/condylomata acuminata (HPV) for patients 12 years and older

A

True
5% cream once daily 3 X weekly application for up to 16 weeks
3.75% cream daily for 8 weeks

45
Q

5% topical Imiquimod is a topical immunomodulating agent approved by the FDA for treatment of superficial small <2cm non-facial superficial BCC if surgery is inappropriate and patient follow up can be assured

A

True

5% cream once daily 5 days/week for 6-12 weeks

46
Q

Imiquimod is a topical immunomodulating agent approved by the FDA for treatment of actinic keratoses on the face and scalp

A

True (poor efficacy for sites other than face and scalp + application more than 3X weekly for these non-scalp and non-facial sites are poorly tolerated)
5% cream twice weekly for 16 weeks to 25cm2 area
5% cream 3 X weekly for 4 weeks to 25cm2 area, to repeat course if patients failed to clear with first course (alternative regimen)
3.75% cream daily to full face/balding scalp for 2 week on/off/on regimen or 3 week on/off/on

47
Q

Imiquimod is a non-nucleoside heterocyclic amine

A

True

48
Q

Imiquimod is an activator of Toll-like receptor-7 (TLR-7) that induces a potent antiviral and antitumour effect in vivo by inducing secretion of a host of inflammatory cytokines such as TNF-alpha, interferons, interleukins

A

True

49
Q

When assessing a superficial BCC site already treated with topical imiquimod, there is no way to ensure the tumour is fully eradicated without a biopsy

A

True (hence the indication to only use imiquimod in low risk tumours as a second line treatment I.e. Superficial subtype, non-facial locations, and small tumours <2cm)

50
Q

Imiquimod-induced hypopigmented or hypertrophic scarring can mask residual tumour underneath the scar

A

True

51
Q

Erythema and ulceration caused by imiquimod can be difficult to differentiate from the tumour

A

True

52
Q

Imiquimod cream should be applied to clean skin prior to normal sleeping hours (bedtime), left in place for approximately 6-10 hours, then washed off with soap and water

A

True (occlusive dressings or wrappings are not recommended because of an increased risk of irritation)

53
Q

Local skin reaction such as redness and burning are common in imiquimod application and may require a rest period of several days

A

True (rest periods should not extend treatment beyond 16 weeks)

54
Q

Clearance of AKs is more common in imiquimod patients who developed intense erythema or other local reactions in treatment areas

A

True

55
Q

Imiquimod is one of many treatment options available for patients with AK who are unable to tolerate other topical first line treatments including 5-FU

A

True

56
Q

Imiquimod is a topical immunomodulating agent with some benefit for cutaneous warts although monotherapy has limited efficacy

A

True

Overnight application 5X weekly

57
Q

Imiquimod monotherapy has limited efficacy on cutaneous warts due to suspected lack of penetrance and absorption of of imiquimod through common wart tissue, and combination of cytodestructive methods such as cryotherapy, salicylic acid, and occlusion Ma enhance the imiquimod efficacy

A

True

58
Q

Imiquimod is not FDA approved for use in children under 12 years of age, but has be reported as an effective treatment (complete clearance) with BD application for 6 months

A

True

59
Q

Imiquimod has been used in the treatment of molluscum contagiousum (pox virus)

A

True

60
Q

Imiquimod is undergoing trial for the treatment of lentigo maligna melanoma

A

True

61
Q

Topical imiquimod is well tolerated, it’s the most frequent adverse reactions being local skin reactions with erythema, pruritus, ulceration and pain with no serious systemic effects

A

True

62
Q

Interferon-gamma has an integral role in genital wart clearance and exhibits indirect antiviral activity with minimal systemic absorption

A

True (although Topical interferon-gamma preparations have not proved to be efficacious over placebo)

63
Q

Bleomycin has antitumour activity

A

True

64
Q

Bleomycin has antibacterial activity

A

True

65
Q

Bleomycin has antiviral activity

A

True

66
Q

Although the mechanism against HPV infection is unclear, Bleomycin acts during the M and G2 phases of the cell cycle by binding to DNA which lead to single-strand breakage

A

True (it is unlikely that Bleomycin binds specifically to HPV)

67
Q

Bleomycin affects protein synthesis which may cause biochemical changes leading to apoptosis and necrosis of keratinocytes

A

True

68
Q

Bleomycin has been associated with detectable plasma concentrations, but there are no reports of systemic toxicity to date

A

True

69
Q

Intralesional Bleomycin has been used for the treatment of verruca vulgaris and has been shown to be more effective than cryotherapy

A

True (not FDA approved)

70
Q

Intralesional Bleomycin is associated with significant localised adverse effects and its use should be limited

A

True

71
Q

Intralesional Bleomycin should not be used in pregnant women

A

True

72
Q

Intralesional Bleomycin should not be used in children

A

True

73
Q

Intralesional Bleomycin should not be used in immunosuppressed patients

A

True

74
Q

Intralesional Bleomycin should not be used in patients with possible vascular compromise

A

True (Raynaud’s phenomenon is an uncommon adverse effect from Intralesional Bleomycin, and remains localised to only the digits that receive the injection)

75
Q

The most common adverse effect of Intralesional Bleomycin is injection site pain

A

True (Techniques to minimise pain include pretreatment local anaesthesia, reconstitution with injectable anaesthetic without adrenaline instead of normal saline, ice packs or vibration analgesia) - ice water soaks for 10-15 mins BD for 4 days may reduce pain after the injection

76
Q

Within 24-72 hours of Intralesional Bleomycin there may be erythema, swelling, and pain before a blackened eschar forms

A

True

77
Q

Scarring is an uncommon adverse effect from Intralesional Bleomycin

A

True

78
Q

Raynaud’s phenomenon is an uncommon adverse effect from Intralesional Bleomycin, and remains localised to only the digits that receive the injection

A

True

79
Q

Permanent loss of the nail plate is an uncommon adverse effect from Intralesional Bleomycin

A

True

80
Q

Persistent nail dystrophy is an uncommon adverse effect from Intralesional Bleomycin

A

True

81
Q

Flagellate hyperpigmentation is an uncommon adverse effect from Intralesional Bleomycin

A

True

82
Q

Each individual wart lesion receives 0.1mL of 1U/mL Bleomycin in a 0.1% solution with normal saline and treatment is repeated every 2-3 weeks until resolution

A

True (no more than a total of 2mL of Bleomycin should be administered per treatment I.e. Approximately 10-20 warts)

83
Q

No more than a total of 2mL of Bleomycin should be administered per treatment I.e. Approximately 10-20 warts

A

True

84
Q

Podophyllin is a crude extract of cytotoxic material from the May apple plant used to treat condyloma acuminata (genital warts)

A

True

85
Q

The most active ingredient and the cytodestructive agent in podophyllin is podophyllotoxin

A

True

86
Q

The concentration of podophyllotoxin (the cytodestructive agent) in office-based podophyllin is not standardised, however the commercial product podofilox in a solution or gel has a stable concentration of 0.5% podophyllotoxin

A

True

87
Q

Even though the concentration of podophyllotoxin in the commercial product podofilox is lower than that found in office-based podophyllin, podofilox does not contain the known mutagens quercetin or kaemperol and is safe to use on an outpatient basis

A

True

88
Q

Podophyllotoxin (active cytodestructive agent on podophyllin) is an Antimitotic agent that arrests cells in metaphase by binding reversibly to tubulin

A

True

89
Q

Even though podofilox (commercial proprietary product) reports greater safety issues especially in women of childbearing potential (no mutagens), office applied podophyllin used as monotherapy or in combination with other cytodestructive therapies can be especially efficacious in pedunculated and cauliflower anogenital condyloma

A

True

90
Q

Podophyllin (office based formula) is contraindicated in pregnancy due to its mutagenic properties and must be used carefully in women of child bearing potential

A

True (birth defects, Fetal death and stillbirth has been reported, and appropriate pregnancy testing is recommended prior to use) - podofilox on the other hand is classified as pregnancy category C

91
Q

Podofilox (commercial proprietary product without mutagens) is classified as pregnancy category C

A

True

92
Q

The most common adverse effects from podophyllin/podofilox are inflammation, burning, erythema, and erosions

A

True

93
Q

Trichloroacetic acid (TCAA) works through the destruction of tissue by causing non-specific hydrolysis of cellular proteins leading to inflammation and cell death

A

True (as the drug is non-specific in its effect on virus-infected cells, care must be taken when applying TCAA so that surrounding tissue is not destroyed)

94
Q

As TCAA is non-specific in its effect on virus-infected cells, care must be taken when applying TCAA so that surrounding tissue is not destroyed

A

True (adequate application is achieved when the wart and surrounding area turn white)

95
Q

TCAA is advantageous over podophyllin as it can be used in treating genital warts in pregnant patients

A

True

96
Q

The major adverse effects following treatment with TCAA are local pain and ulceration

A

True

97
Q

Cantharidin is a vesiculating agent derived from the ‘blister beetle’, also known as the Spanish fly

A

True

98
Q

Cantharidin acts by interfering with mitochondria leading to epidermal cell death, acantholysis and clinical blister formation (no direct antiviral effect)

A

True

99
Q

Cantharidin has no direct antiviral effect

A

True

100
Q

Cantharidin is limited to topical treatment of verruca vulgaris with cure rates as high as 80% for common, plantar and periungual warts

A

True (solution applied directly to the wart with the wooden end of a cotton applicator or toothpick, and lesion occluded for 4-24 hours with adhesive tape; a blister usually forms within 6-48 hours and often heals within 1 week) - retreatment at 1-3 week intervals

101
Q

The benefits of topical cantharidin on verruca vulgaris is that it is painless and there is no scarring

A

True

102
Q

The major adverse effect of topical cantharidin is blister-associated pain

A

True

103
Q

Less commonly, a ring wart (annular wart formed at the periphery of a resolving blister) is induced by cantharidin

A

True (less frequently also noted post cryotherapy)

104
Q

Topical cantharidin has also been used for molluscum contagiousum in a similar fashion as for verruca vulgaris

A

True (generally without occlusion, except for large papules or persistent lesions)

105
Q

Combination therapy using topical cantharidin and imiquimod for the treatment of molluscum contagiousum in children has been effective and well tolerated

A

True

106
Q

Salicylic acid is a topical keratolytic agent that is a common component of OTC verruca vulgaris treatments

A

True (ranging in concentrations between 10% and 60%)

107
Q

Salicylic acid is recommended for use in treatment of warts located on the hands and feet

A

True (for best results, soak the wart in warm water for 5 mins and remove the dead tissue it’s an emery board or pumice stone, followed by application of salicylic acid and occlusion)

108
Q

Among all local treatment for cutaneous non-genital warts in immunocompetent patients, the best available evidence supports the use of simple topical treatment containing salicylic acid

A

True

109
Q

5-FU is a pyrimidine analog with cytotoxic effects that penetrates abnormal skin to a greater extent than normal skin

A

True

110
Q

5-FU has demonstrated some degree of efficacy in the treatment of resistant genital condylomas/warts, verruca plana and verruca vulgaris

A

True (once weekly application is as effective as daily treatment, and with fewer adverse effects)
NB. FDA approval is for multiple AKs and superficial BCCs

111
Q

Adverse effects from topical 5-FU include erythema, oedema, possible erosive dermatitis and mucositis

A

True

112
Q

Sinecathechin is a FDA approved topical high grade green tea polyphenol extract for treatment of external genital and perianal warts

A

True

113
Q

Sinecathechin contain epigallocathechin gallate which protects cells from oxidative damage, induces apoptosis, and inhibits telomerase activity

A

True

114
Q

Adverse effects of sinecathechin include erythema, pruritus, ulceration, pain and oedema

A

True